Childhood vaccinations

Vaccination is the term used for getting a vaccine, that is, actually getting the injection or taking an oral vaccine dose. Vaccines train your immune system to quickly recognize and clear out germs (bacteria and viruses) that can cause serious illnesses. Vaccines strengthen your immune system a bit like exercise strengthens muscles. Below is the Recommended Child and Adolescent Immunization Schedule for ages 18 years or younger, United States, 2022. The Centers for Disease Control and Prevention (CDC) recommends routine vaccination or immunization to prevent 17 vaccine-preventable diseases that occur in infants, children, adolescents, or adults. The schedules shown below is recommended by the Advisory Committee on Immunization Practices (https://www.cdc.gov/vaccines/acip/index.html) and approved by the Centers for Disease Control and Prevention (https://www.cdc.gov), American Academy of Pediatrics (https://www.aap.org/en-us/Pages/Default.aspx), American Academy of Family Physicians (https://www.aafp.org/home.html), American College of Obstetricians and Gynecologists (https://www.acog.org), and American College of Nurse-Midwives (https://www.midwife.org/default.aspx).

Diphtheria (Can be prevented by Tdap vaccination)

Diphtheria is a very contagious bacterial disease that affects the respiratory system, including the lungs. Diphtheria bacteria can be spread from person to person by direct contact with droplets from an infected person’s cough or sneeze. When people are infected, the bacteria can produce a toxin (poison) in the body that can cause a thick coating in the back of the nose or throat that makes it hard to breathe or swallow. Effects from this toxin can also lead to swelling of the heart muscle and, in some cases, heart failure. In serious cases, the illness can cause coma, paralysis, or even death.

Hepatitis A (Can be prevented by HepA vaccination)

Hepatitis A is an infection in the liver caused by hepatitis A virus. The virus is spread primarily person-to-person through the fecal-oral route. In other words, the virus is taken in by mouth from contact with objects, food, or drinks contaminated by the feces (stool) of an infected person. Symptoms can include fever, tiredness, poor appetite, vomiting, stomach pain, and sometimes jaundice (when skin and eyes turn yellow). An infected person may have no symptoms, may have mild illness for a week or two, may have severe illness for several months, or may rarely develop liver failure and die from the infection. In the U.S., about 100 people a year die from hepatitis A.

Hepatitis B (Can be prevented by HepB vaccination)

Hepatitis B causes a flu-like illness with loss of appetite, nausea, vomiting, rashes, joint pain, and jaundice. Symptoms of acute hepatitis B include fever, fatigue, loss of appetite, nausea, vomiting, pain in joints and stomach, dark urine, grey-colored stools, and jaundice (when skin and eyes turn yellow).

Human Papillomavirus (Can be prevented by HPV vaccination)

Human papillomavirus is a common virus. HPV is most common in people in their teens and early 20s. About 14 million people, including teens, become infected with HPV each year. HPV infection can cause cervical, vaginal, and vulvar cancers in women and penile cancer in men. HPV can also cause anal cancer, oropharyngeal cancer (back of the throat), and genital warts in both men and women.

Influenza (Can be prevented by annual flu vaccination)

Influenza is a highly contagious viral infection of the nose, throat, and lungs. The virus spreads easily through droplets when an infected person coughs or sneezes and can cause mild to severe illness. Typical symptoms include a sudden high fever, chills, a dry cough, headache, runny nose, sore throat, and muscle and joint pain. Extreme fatigue can last from several days to weeks. Influenza may lead to hospitalization or even death, even among previously healthy children.

Measles (Can be prevented by MMR vaccination)

Measles is one of the most contagious viral diseases. Measles virus is spread by direct contact with the airborne respiratory droplets of an infected person. Measles is so contagious that just being in the same room after a person who has measles has already left can result in infection. Symptoms usually include a rash, fever, cough, and red, watery eyes. Fever can persist, rash can last for up to a week, and coughing can last about 10 days. Measles can also cause pneumonia, seizures, brain damage, or death.

Meningococcal Disease (Can be prevented by meningococcal vaccination)

Meningococcal disease has two common outcomes: meningitis (infection of the lining of the brain and spinal cord) and bloodstream infections. The bacteria that cause meningococcal disease spread through the exchange of nose and throat droplets, such as when coughing, sneezing, or kissing. Symptoms include sudden onset of fever, headache, and stiff neck. With bloodstream infection, symptoms also include a dark purple rash. About one of every ten people who gets the disease dies from it. Survivors of meningococcal disease may lose their arms or legs, become deaf, have problems with their nervous systems, become developmentally disabled, or suffer seizures or strokes.

Mumps (Can be prevented by MMR vaccination)

Mumps is an infectious disease caused by the mumps virus, which is spread in the air by a cough or sneeze from an infected person. A child can also get infected with mumps by coming in contact with a contaminated object, like a toy. The mumps virus causes swollen salivary glands under the ears or jaw, fever, muscle aches, tiredness, abdominal pain, and loss of appetite. Severe complications for children who get mumps are uncommon, but can include meningitis (infection of the covering of the brain and spinal cord), encephalitis (inflammation of the brain), permanent hearing loss, or swelling of the testes, which rarely results in decreased fertility.

Pertussis (Whooping Cough) (Can be prevented by Tdap vaccination)

Pertussis spreads very easily through coughing and sneezing. It can cause a bad cough that makes someone gasp for air after coughing fits. This cough can last for many weeks, which can make preteens and teens miss school and other activities. Pertussis can be deadly for babies who are too young to receive the vaccine. Often babies get whooping cough from their older brothers or sisters, like preteens or teens, or other people in the family. Babies with pertussis can get pneumonia, have seizures, become brain damaged, or even die. About half of children under 1 year of age who get pertussis must be hospitalized.

Pneumococcal Disease (Can be prevented by pneumococcal vaccination)

Pneumonia is an infection of the lungs that can be caused by the bacteria called pneumococcus. These bacteria can cause other types of infections too, such as ear infections, sinus infections, meningitis (infection of the lining of the brain and spinal cord), and bloodstream infections. Sinus and ear infections are usually mild and are much more common than the more serious forms of pneumococcal disease. However, in some cases pneumococcal disease can be fatal or result in long-term problems, like brain damage, and hearing loss. The bacteria that cause pneumococcal disease spread when people cough or sneeze. Many people have the bacteria in their nose or throat at one time or another without being ill—this is known as being a carrier.

Polio (Can be prevented by IPV vaccination)

Polio is caused by a virus that lives in an infected person’s throat and intestines. It spreads through contact with the stool of an infected person and through droplets from a sneeze or cough. Symptoms typically include sore throat, fever, tiredness, nausea, headache, or stomach pain. In about 1% of cases, polio can cause paralysis. Among those who are paralyzed, About 2 to 10 children out of 100 die because the virus affects the muscles that help them breathe.

Rubella (German Measles) (Can be prevented by MMR vaccination)

Rubella is caused by a virus that is spread through coughing and sneezing. In children rubella usually causes a mild illness with fever, swollen glands, and a rash that lasts about 3 days. Rubella rarely causes serious illness or complications in children, but can be very serious to a baby in the womb. If a pregnant woman is infected, the result to the baby can be devastating, including miscarriage, serious heart defects, mental retardation and loss of hearing and eye sight.

Tetanus (Lockjaw) (Can be prevented by Tdap vaccination)

Tetanus mainly affects the neck and belly. When people are infected, the bacteria produce a toxin (poison) that causes muscles to become tight, which is very painful. This can lead to “locking” of the jaw so a person cannot open his or her mouth, swallow, or breathe. The bacteria that cause tetanus are found in soil, dust, and manure. The bacteria enter the body through a puncture, cut, or sore on the skin. Complete recovery from tetanus can take months. One to two out of 10 people who get tetanus die from the disease.

Varicella (Chickenpox) (Can be prevented by varicella vaccination)

Chickenpox is caused by the varicella zoster virus. Chickenpox is very contagious and spreads very easily from infected people. The virus can spread from either a cough, sneeze. It can also spread from the blisters on the skin, either by touching them or by breathing in these viral particles. Typical symptoms of chickenpox include an itchy rash with blisters, tiredness, headache and fever. Chickenpox is usually mild, but it can lead to severe skin infections, pneumonia, encephalitis (brain swelling), or even death.

Table 1. Vaccine-Preventable Diseases and the Vaccines that Prevent Them

Disease	Vaccine	Disease spread by	Disease symptoms	Disease complications
Chickenpox	Varicella vaccine protects against chickenpox.	Air, direct contact	Rash, tiredness, headache, fever	Infected blisters, bleeding disorders, encephalitis (brain swelling), pneumonia (infection in the lungs)
Diphtheria	DTaP* vaccine protects against diphtheria.	Air, direct contact	Sore throat, mild fever, weakness, swollen glands in neck	Swelling of the heart muscle, heart failure, coma, paralysis, death
Haemophilus influenzae infections	Hib vaccine protects against Haemophilus influenzae type b.	Air, direct contact	May be no symptoms unless bacteria enter the blood	Meningitis (infection of the covering around the brain and spinal cord), intellectual disability, epiglottitis (life-threatening infection that can block the windpipe and lead to serious breathing problems), pneumonia (infection in the lungs), death
Hepatitis A	HepA vaccine protects against hepatitis A.	Direct contact, contaminated food or water	May be no symptoms, fever, stomach pain, loss of appetite, fatigue, vomiting, jaundice (yellowing of skin and eyes), dark urine	Liver failure, arthralgia (joint pain), kidney, pancreatic, and blood disorders
Hepatitis B	HepB vaccine protects against hepatitis B.	Contact with blood or body fluids	May be no symptoms, fever, headache, weakness, vomiting, jaundice (yellowing of skin and eyes), joint pain	Chronic liver infection, liver failure, liver cancer
Influenza (Flu)	Flu vaccine protects against influenza.	Air, direct contact	Fever, muscle pain, sore throat, cough, extreme fatigue	Pneumonia (infection in the lungs)
Measles	MMR** vaccine protects against measles.	Air, direct contact	Rash, fever, cough, runny nose, pinkeye	Encephalitis (brain swelling), pneumonia (infection in the lungs), death
Mumps	MMR**vaccine protects against mumps.	Air, direct contact	Swollen salivary glands (under the jaw), fever, headache, tiredness, muscle pain	Meningitis (infection of the covering around the brain and spinal cord) , encephalitis (brain swelling), inflam mation of testicles or ovaries, deafness
Pertussis	DTaP* vaccine protects against pertussis (whooping cough).	Air, direct contact	Severe cough, runny nose, apnea (a pause in breathing in infants)	Pneumonia (infection in the lungs), death
Polio	IPV vaccine protects against polio.	Air, direct contact, through the mouth	May be no symptoms, sore throat, fever, nausea, headache	Paralysis, death
Pneumococcal	PCV13 vaccine protects against pneumococcus.	Air, direct contact	May be no symptoms, pneumonia (infection in the lungs)	Bacteremia (blood infection), meningitis (infection of the covering around the brain and spinal cord), death
Rotavirus	RV vaccine protects against rotavirus.	Through the mouth	Diarrhea, fever, vomiting	Severe diarrhea, dehydration
Rubella	MMR** vaccine protects against rubella.	Air, direct contact	Children infected with rubella virus sometimes have a rash, fever, swollen lymph nodes	Very serious in pregnant women—can lead to miscarriage, stillbirth, premature delivery, birth defects
Tetanus	DTaP* vaccine protects against tetanus.	Exposure through cuts in skin	Stiffness in neck and abdominal muscles, difficulty swallowing, muscle spasms, fever	Broken bones, breathing difficulty, death

Footnotes: For Advisory Committee on Immunization Practices (ACIP) Vaccine Recommendations and Guidelines go here: https://www.cdc.gov/vaccines/hcp/acip-recs

* DTaP combines protection against diphtheria, tetanus, and pertussis.

** MMR combines protection against measles, mumps, and rubella.

[Source ¹ ]

Table 2. Childhood vaccinations from birth to 15 months

Footnotes: YELLOW = Range of recommended ages for all children; GREEN = Range of recommended ages for catch-up immunization; PURPLE = Range of recommended ages for certain high-risk groups; BLUE = Recommended based on shared clinical decision-making or *can be used in this age group; GREY = No recommendation/Not applicable

For calculating intervals between doses, 4 weeks = 28 days. Intervals of ≥4 months are determined by calendar months.
Vaccine doses administered ≤4 days before the minimum age or interval are considered valid. Doses of any vaccine administered ≥5 days earlier than the minimum age or minimum interval should not be counted as valid and should be repeated as age-appropriate. The repeat dose should be spaced after the invalid dose by the recommended minimum interval.

[Source ² ]

Table 3. Childhood vaccinations from 18 months to 18 years

[Source ² ]

Table 4. Catch-up immunization schedule for children aged 4 months through 6 years who start late or who are more than 1 month behind, United States, 2022

Footnotes: Administer recommended vaccines if immunization history is incomplete or unknown. Do not restart or add doses to vaccine series for extended intervals between doses. When a vaccine is not administered at the recommended age, administer at a subsequent visit. The use of trade names is for identification purposes only and does not imply endorsement by the Advisory Committee on Immunization Practices or CDC.

[Source ³ ]

Table 5. Catch-up immunization schedule for children and adolescents age 7 through 18 years who start late or who are more than 1 month behind, United States, 2022

[Source ³ ]

Are vaccines safe?

Yes. Vaccines are very safe. The United States’ long-standing vaccine safety system ensures that vaccines are as safe as possible. Currently, the United States has the safest vaccine supply in its history. Millions of children safely receive vaccines each year. The most common side effects are typically very mild, such as pain or swelling at the injection site.

Childhood vaccinations list

List of Vaccines Used in United States ⁴:

Adenovirus
Anthrax
- AVA (BioThrax)
Cholera
- Vaxchora
Diphtheria
- DTaP (Daptacel, Infanrix)
- Td (Tenivac, generic)
- DT (-generic-)
- Tdap (Adacel, Boostrix)
- DTaP-IPV (Kinrix, Quadracel)
- DTaP-HepB-IPV (Pediarix)
- DTaP-IPV/Hib (Pentacel)
Hepatitis A
- HepA (Havrix, Vaqta)
- HepA-HepB (Twinrix)
Hepatitis B
- HepB (Engerix-B, Recombivax HB, Heplisav-B)
- DTaP-HepB-IPV (Pediarix)
- HepA-HepB (Twinrix)
- DTaP-IPV-Hib-HepB (Vaxelis)
Haemophilus influenzae type b (Hib)
- Hib (ActHIB, PedvaxHIB, Hiberix)
- DTaP-IPV/Hib (Pentacel)
- DTaP-IPV-Hib-HepB (Vaxelis)
Human Papillomavirus (HPV)
- HPV9 (Gardasil 9) (For scientific papers, the preferred abbreviation is 9vHPV)
Seasonal Influenza (Flu) only
- IIV* (Afluria, Fluad, Flublok, Flucelvax, FluLaval, Fluarix, Fluvirin, Fluzone, Fluzone High-Dose, Fluzone Intradermal)
- *There are various acronyms for inactivated flu vaccines – IIV3, IIV4, RIV3, RIV4 and ccIIV4.
- LAIV (FluMist)
Japanese Encephalitis
- JE (Ixiaro)
Measles
- MMR (M-M-R II)
- MMRV (ProQuad)
Meningococcal
- MenACWY (Menactra, Menveo)
- MenB (Bexsero, Trumenba)
Mumps
- MMR (M-M-R II)
- MMRV (ProQuad)
Pertussis
- DTaP (Daptacel, Infanrix)
- Tdap (Adacel, Boostrix)
- DTaP-IPV (Kinrix, Quadracel)
- DTaP-HepB-IPV (Pediarix)
- DTaP-IPV/Hib (Pentacel)
Pneumococcal
- PCV13 (Prevnar13)
- PCV15 (Vaxneuvance)
- PCV20 (Prevnar20)
- PPSV23 (Pneumovax 23)
Polio
- Polio (Ipol)
- DTaP-IPV (Kinrix, Quadracel)
- DTaP-HepB-IPV (Pediarix)
- DTaP-IPV/Hib (Pentacel)
- DTaP-IPV-Hib-HepB (Vaxelis)
Rabies
- Rabies (Imovax Rabies, RabAvert)
Rotavirus
- RV1 (Rotarix)
- RV5 (RotaTeq)
Rubella
- MMR (M-M-R II)
- MMRV (ProQuad)
Shingles
- RZV (Shingrix)
Smallpox
- Vaccinia (ACAM2000):
Tetanus
- DTaP (Daptacel, Infanrix)
- Td (Tenivac, generic)
- DT (-generic-)
- Tdap (Adacel, Boostrix)
- DTaP-IPV (Kinrix, Quadracel)
- DTaP-HepB-IPV (Pediarix)
- DTaP-IPV/Hib (Pentacel)
- DTaP-IPV-Hib-HepB (Vaxelis)
Tuberculosis
Typhoid Fever
- Typhoid Oral (Vivotif)
- Typhoid Polysaccharide (Typhim Vi)
Varicella
- VAR (Varivax)
- MMRV (ProQuad):
Yellow Fever
- YF (YF-Vax)

Table 6. Vaccines in the child and adolescent immunization schedule

Vaccines	Abbreviations	Trade Names
Diphtheria, tetanus, and acellular pertussis vaccine	DTaP	Daptacel^® Infanrix^®
Diphtheria, tetanus vaccine	DT	No Trade Name
Haemophilus influenzae type B vaccine	Hib (PRP-T) Hib (PRP-OMP)	ActHIB^® Hiberix^® PedvaxHIB^®
Hepatitis A vaccine	HepA	Havrix^® Vaqta^®
Hepatitis B vaccine	HepB	Engerix-B^® Recombivax HB^®
Human papillomavirus vaccine	HPV	Gardasil 9^®
Influenza vaccine (inactivated)	IIV	Multiple
Influenza vaccine (live, attenuated)	LAIV	FluMist^® Quadrivalent
Measles, mumps, and rubella vaccine	MMR	M-M-R^® II
Meningococcal serogroups A, C, W, Y vaccine	MenACWY-D MenACWY-CRM	Menactra^® Menveo^®
Meningococcal serogroup B vaccine	MenB-4C MenB-FHbp	Bexsero^® Trumenba^®
Pneumococcal 13-valent conjugate vaccine	PCV13	Prevnar 13^®
Pneumococcal 23-valent polysaccharide vaccine	PPSV23	Pneumovax^® 23
Poliovirus vaccine (inactivated)	IPV	IPOL^®
Rotavirus vaccine	RV1 RV5	Rotarix^® RotaTeq^®
Tetanus, diphtheria, and acellular pertussis vaccine	Tdap	Adacel^® Boostrix^®
Tetanus and diphtheria vaccine	Td	Tenivac^® TDvax™
Varicella vaccine	VAR	Varivax^®

[Source ⁵ ]

Table 7. Combination vaccines (use combination vaccines instead of separate injections when appropriate)

Vaccines	Abbreviations	Trade Names
DTaP, hepatitis B, and inactivated poliovirus vaccine	DTaP-HepB-IPV	Pediarix^®
DTaP, inactivated poliovirus, and Haemophilus influenzae type B vaccine	DTaP-IPV/Hib	Pentacel^®
DTaP and inactivated poliovirus vaccine	DTaP-IPV	Kinrix^® Quadracel^®
Measles, mumps, rubella, and varicella vaccines	MMRV	ProQuad^®

[Source ⁵ ]

List of childhood vaccines

Diphtheria, tetanus, and pertussis (DTaP) vaccination

Minimum age: 6 weeks (4 years for Kinrix or Quadracel)

Routine vaccination

5-dose series at 2, 4, 6, 15–18 months, 4–6 years
Prospectively: Dose 4 may be administered as early as age 12 months if at least 6 months have elapsed since dose 3.
Retrospectively: A 4th dose that was inadvertently administered as early as 12 months may be counted if at least 4 months have elapsed since dose 3.

Catch-up vaccination

Dose 5 is not necessary if dose 4 was administered at age 4 years or older and at least 6 months after dose 3.
For other catch-up guidance, see Tables 4 and 5.

Haemophilus influenzae type b (Hib) vaccination

Minimum age: 6 weeks

Routine vaccination

ActHIB, Hiberix, or Pentacel: 4-dose series at 2, 4, 6, 12–15 months
PedvaxHIB: 3-dose series at 2, 4, 12–15 months

Catch-up vaccination

Dose 1 at 7–11 months: Administer dose 2 at least 4 weeks later and dose 3 (final dose) at 12–15 months or 8 weeks after dose 2 (whichever is later).
Dose 1 at 12–14 months: Administer dose 2 (final dose) at least 8 weeks after dose 1.
Dose 1 before 12 months and dose 2 before 15 months: Administer dose 3 (final dose) 8 weeks after dose 2.
2 doses of PedvaxHIB before 12 months: Administer dose 3 (final dose) at 12–59 months and at least 8 weeks after dose 2.
Unvaccinated at 15–59 months: 1 dose
Previously unvaccinated children age 60 months or older who are not considered high risk do not require catch-up vaccination.
For other catch-up guidance, see Table 4.

Special situations

Chemotherapy or radiation treatment:
- 12–59 months
  - Unvaccinated or only 1 dose before age 12 months: 2 doses, 8 weeks apart
  - 2 or more doses before age 12 months: 1 dose at least 8 weeks after previous dose
- Doses administered within 14 days of starting therapy or during therapy should be repeated at least 3 months after therapy completion.
Hematopoietic stem cell transplant (HSCT):
- 3-dose series 4 weeks apart starting 6 to 12 months after successful transplant regardless of Hib vaccination history
Anatomic or functional asplenia (including sickle cell disease):
- 12–59 months
  - Unvaccinated or only 1 dose before age 12 months: 2 doses, 8 weeks apart
  - 2 or more doses before age 12 months: 1 dose at least 8 weeks after previous dose
- Unvaccinated* persons age 5 years or older
  - 1 dose
Elective splenectomy:
- Unvaccinated* persons age 15 months or older
  - 1 dose (preferably at least 14 days before procedure)
HIV infection:
- 12–59 months
  - Unvaccinated or only 1 dose before age 12 months: 2 doses, 8 weeks apart
  - 2 or more doses before age 12 months: 1 dose at least 8 weeks after previous dose
- Unvaccinated* persons age 5–18 years
  - 1 dose
Immunoglobulin deficiency, early component complement deficiency:
- 12–59 months
  - Unvaccinated or only 1 dose before age 12 months: 2 doses, 8 weeks apart
  - 2 or more doses before age 12 months: 1 dose at least 8 weeks after previous dose

*Unvaccinated = Less than routine series (through 14 months) OR no doses (15 months or older)

Hepatitis A vaccination

Minimum age: 12 months for routine vaccination

Routine vaccination

2-dose series (minimum interval: 6 months) beginning at age
12 months

Catch-up vaccination

Unvaccinated persons through 18 years should complete a 2-dose series (minimum interval: 6 months).
Persons who previously received 1 dose at age 12 months or older should receive dose 2 at least 6 months after dose 1.
Adolescents 18 years and older may receive the combined HepA and HepB vaccine, Twinrix®, as a 3-dose series (0, 1, and 6 months) or 4-dose series (0, 7, and 21–30 days, followed by a dose at 12 months).

International travel

Persons traveling to or working in countries with high or intermediate endemic hepatitis A:
- Infants age 6–11 months: 1 dose before departure; revaccinate with 2 doses, separated by at least 6 months, between 12 and 23 months of age
- Unvaccinated age 12 months and older: Administer dose 1 as soon as travel is considered.

Hepatitis B vaccination

Minimum age: birth

Birth dose (monovalent HepB vaccine only)

Mother is HBsAg-negative: 1 dose within 24 hours of birth for all medically stable infants ≥2,000 grams. Infants
- <2,000 grams: administer 1 dose at chronological age 1 month or hospital discharge.
Mother is HBsAg-positive:
- Administer HepB vaccine and hepatitis B immune globulin (HBIG) (in separate limbs) within 12 hours of birth, regardless of birth weight. For infants <2,000 grams, administer 3 additional doses of vaccine (total of 4 doses) beginning at age 1 month.
- Test for HBsAg and anti-HBs at age 9–12 months. If HepB series is delayed, test 1–2 months after final dose.
Mother’s HBsAg status is unknown:
- Administer HepB vaccine within 12 hours of birth, regardless of birth weight.
- For infants <2,000 grams, administer HBIG in addition to HepB vaccine (in separate limbs) within 12 hours of birth. Administer 3 additional doses of vaccine (total of 4 doses) beginning at age 1 month.
- Determine mother’s HBsAg status as soon as possible. If mother is HBsAg-positive, administer HBIG to infants ≥2,000 grams as soon as possible, but no later than 7 days of age.

Routine series

3-dose series at 0, 1–2, 6–18 months (use monovalent HepB vaccine for doses administered before age 6 weeks)
Infants who did not receive a birth dose should begin the series as soon as feasible (see Table 2).
Administration of 4 doses is permitted when a combination vaccine containing HepB is used after the birth dose.
Minimum age for the final (3rd or 4th ) dose: 24 weeks
Minimum intervals: dose 1 to dose 2: 4 weeks / dose 2 to dose 3: 8 weeks / dose 1 to dose 3: 16 weeks (when 4 doses are administered, substitute “dose 4” for “dose 3” in these calculations)

Catch-up vaccination

Unvaccinated persons should complete a 3-dose series at 0, 1–2, 6 months.
Adolescents age 11–15 years may use an alternative 2-dose schedule with at least 4 months between doses (adult formulation Recombivax HB only).
Adolescents 18 years and older may receive a 2-dose series of HepB (Heplisav-B®) at least 4 weeks apart.
Adolescents 18 years and older may receive the combined HepA and HepB vaccine, Twinrix, as a 3-dose series (0, 1, and 6 months) or 4-dose series (0, 7, and 21–30 days, followed by a dose at 12 months).
For other catch-up guidance, see see Table 4.

Special situations

Revaccination is not generally recommended for persons with a normal immune status who were vaccinated as infants, children, adolescents, or adults.
Revaccination may be recommended for certain populations, including:
- Infants born to HBsAg-positive mothers
- Hemodialysis patients
- Other immunocompromised persons

Human papillomavirus (HPV) vaccination

Minimum age: 9 years

Routine and catch-up vaccination

HPV vaccination routinely recommended at age 11–12 years (can start at age 9 years) and catch-up HPV vaccination recommended for all persons through age 18 years if not adequately vaccinated
2- or 3-dose series depending on age at initial vaccination:
- Age 9 through 14 years at initial vaccination: 2-dose series at 0, 6–12 months (minimum interval: 5 months; repeat dose if administered too soon)
- Age 15 years or older at initial vaccination: 3-dose series at 0, 1–2 months, 6 months (minimum intervals: dose 1 to dose 2: 4 weeks / dose 2 to dose 3: 12 weeks / dose 1 to dose 3: 5 months; repeat dose if administered too soon)
If completed valid vaccination series with any HPV vaccine, no additional doses needed

Special situations

Immunocompromising conditions, including HIV infection: 3-dose series as above
History of sexual abuse or assault: Start at age 9 years
Pregnancy: HPV vaccination not recommended until after pregnancy; no intervention needed if vaccinated while pregnant; pregnancy testing not needed before vaccination

Influenza vaccination

Minimum age: 6 months [IIV], 2 years [LAIV], 18 years [recombinant influenza vaccine, RIV]

Routine vaccination

Use any influenza vaccine appropriate for age and health status annually:
- 2 doses, separated by at least 4 weeks, for children age 6 months–8 years who have received fewer than 2 influenza vaccine doses before July 1, 2019, or whose influenza vaccination history is unknown (administer dose 2 even if the child turns 9 between receipt of dose 1 and dose 2)
- 1 dose for children age 6 months–8 years who have received at least 2 influenza vaccine doses before July 1, 2019
- 1 dose for all persons age 9 years and older
For the 2020–21 season, see the 2020–21 Advisory Committee on Immunization Practices influenza vaccine recommendations.

Special situations

Egg allergy, hives only: Any influenza vaccine appropriate for age and health status annually
Egg allergy with symptoms other than hives (e.g., angioedema, respiratory distress, need for emergency medical services or epinephrine): Any influenza vaccine appropriate for age and health status annually in medical setting under supervision of health care provider who can recognize and manage severe allergic reactions
LAIV should not be used in persons with the following conditions or situations:
- History of severe allergic reaction to a previous dose of any influenza vaccine or to any vaccine component (excluding egg, see details above)
- Receiving aspirin or salicylate-containing medications
- Age 2–4 years with history of asthma or wheezing
- Immunocompromised due to any cause (including medications and HIV infection)
- Anatomic or functional asplenia
- Cochlear implant
- Cerebrospinal fluid-oropharyngeal communication
- Close contacts or caregivers of severely immunosuppressed persons who require a protected environment
- Pregnancy
- Received influenza antiviral medications within the previous 48 hours

Measles, mumps, and rubella (MMR) vaccination

Minimum age: 12 months for routine vaccination

Routine vaccination

2-dose series at 12–15 months, 4–6 years
Dose 2 may be administered as early as 4 weeks after dose 1.

Catch-up vaccination

Unvaccinated children and adolescents: 2-dose series at least 4 weeks apart
The maximum age for use of MMRV is 12 years.

Special situations

International travel
- Infants age 6–11 months: 1 dose before departure; revaccinate with 2-dose series with dose 1 at 12–15 months (12 months for children in high-risk areas) and dose 2 as early as 4 weeks later.
- Unvaccinated children age 12 months and older: 2-dose series at least 4 weeks apart before departure

Meningococcal serogroup A,C,W,Y vaccination

Minimum age: 2 months [MenACWY-CRM, Menveo], 9 months [MenACWY-D, Menactra]

Routine vaccination

2-dose series at 11–12 years, 16 years

Catch-up vaccination

Age 13–15 years: 1 dose now and booster at age 16–18 years (minimum interval: 8 weeks)
Age 16–18 years: 1 dose

Special situations

Anatomic or functional asplenia (including sickle cell disease), HIV infection, persistent complement component deficiency, complement inhibitor (e.g., eculizumab, ravulizumab) use:
- Menveo
  - Dose 1 at age 8 weeks: 4-dose series at 2, 4, 6, 12 months
  - Dose 1 at age 7–23 months: 2-dose series (dose 2 at least 12 weeks after dose 1 and after age 12 months)
  - Dose 1 at age 24 months or older: 2-dose series at least 8 weeks apart
- Menactra
  - Persistent complement component deficiency or complement inhibitor use:
    - Age 9–23 months: 2-dose series at least 12 weeks apart
    - Age 24 months or older: 2-dose series at least 8 weeks apart
  - Anatomic or functional asplenia, sickle cell disease, or HIV infection:
    - Age 9–23 months: Not recommended
    - Age 24 months or older: 2-dose series at least 8 weeks apart
    - Menactra must be administered at least 4 weeks after completion of PCV13 series.
Travel in countries with hyperendemic or epidemic meningococcal disease, including countries in the African meningitis belt or during the Hajj:
- Children less than age 24 months:
  - Menveo (age 2–23 months):
    - Dose 1 at 8 weeks: 4-dose series at 2, 4, 6, 12 months
    - Dose 1 at 7–23 months: 2-dose series (dose 2 at least 12 weeks after dose 1 and after age 12 months)
  - Menactra (age 9–23 months):
    - 2-dose series (dose 2 at least 12 weeks after dose 1; dose 2 may be administered as early as 8 weeks after dose 1 in travelers)
- Children age 2 years or older: 1 dose Menveo or Menactra
First-year college students who live in residential housing (if not previously vaccinated at age 16 years or older) or military recruits:
- 1 dose Menveo or Menactra
Adolescent vaccination of children who received MenACWY prior to age 10 years:
- Children for whom boosters are recommended because of an ongoing increased risk of meningococcal disease (e.g., those with complement deficiency, HIV, or asplenia): Follow the booster schedule for persons at increased risk (see below).
- Children for whom boosters are not recommended (e.g., those who received a single dose for travel to a country where meningococcal disease is endemic): Administer MenACWY according to the recommended adolescent schedule with dose 1 at age 11–12 years and dose 2 at age 16 years.

Note: Menactra should be administered either before or at the same time as DTaP. For MenACWY booster dose recommendations for groups listed under “Special situations” and in an outbreak setting.

Meningococcal serogroup B vaccination

Minimum age: 10 years [MenB-4C, Bexsero; MenB-FHbp, Trumenba]

Shared clinical decision-making

Adolescents not at increased risk age 16–23 years (preferred age 16–18 years) based on shared clinical decision-making:
- Bexsero: 2-dose series at least 1 month apart
- Trumenba: 2-dose series at least 6 months apart; if dose 2 is administered earlier than 6 months, administer a 3rd dose at least 4 months after dose 2.

Special situations

Anatomic or functional asplenia (including sickle cell disease), persistent complement component deficiency, complement inhibitor (e.g., eculizumab, ravulizumab) use:
- Bexsero: 2-dose series at least 1 month apart
- Trumenba: 3-dose series at 0, 1–2, 6 months

Bexsero and Trumenba are not interchangeable; the same product should be used for all doses in a series.

Pneumococcal vaccination

Minimum age: 6 weeks [PCV13], 2 years [PPSV23]

Routine vaccination with PCV13

4-dose series at 2, 4, 6, 12–15 months

Catch-up vaccination with PCV13

1 dose for healthy children age 24–59 months with any incomplete* PCV13 series
For other catch-up guidance, see Tables 4 and 5.

Special situations

High-risk conditions below: When both PCV13 and PPSV23 are indicated, administer PCV13 first. PCV13 and PPSV23 should not be administered during the same visit.
Chronic heart disease (particularly cyanotic congenital heart disease and cardiac failure), chronic lung disease (including asthma treated with high-dose, oral corticosteroids), diabetes mellitus:
- Age 2–5 years
  - Any incomplete* series with:
    - 3 PCV13 doses: 1 dose PCV13 (at least 8 weeks after any prior PCV13 dose)
    - Less than 3 PCV13 doses: 2 doses PCV13 (8 weeks after the most recent dose and administered 8 weeks apart)
  - No history of PPSV23: 1 dose PPSV23 (at least 8 weeks after any prior PCV13 dose)
- Age 6–18 years
  - No history of PPSV23: 1 dose PPSV23 (at least 8 weeks after any prior PCV13 dose)
Cerebrospinal fluid leak, cochlear implant:
- Age 2–5 years
  - Any incomplete* series with:
    - 3 PCV13 doses: 1 dose PCV13 (at least 8 weeks after any prior PCV13 dose)
    - Less than 3 PCV13 doses: 2 doses PCV13 (8 weeks after the most recent dose and administered 8 weeks apart)
  - No history of PPSV23: 1 dose PPSV23 (at least 8 weeks after any prior PCV13 dose)
- Age 6–18 years
  - No history of either PCV13 or PPSV23: 1 dose PCV13, 1 dose PPSV23 at least 8 weeks later
  - Any PCV13 but no PPSV23: 1 dose PPSV23 at least 8 weeks after the most recent dose of PCV13
  - PPSV23 but no PCV13: 1 dose PCV13 at least 8 weeks after the most recent dose of PPSV23
Sickle cell disease and other hemoglobinopathies; anatomic or functional asplenia; congenital or acquired immunodeficiency; HIV infection; chronic renal failure; nephrotic syndrome; malignant neoplasms, leukemias, lymphomas, Hodgkin disease, and other diseases associated with treatment with immunosuppressive drugs or radiation therapy; solid organ transplantation; multiple myeloma:
- Age 2–5 years
  - Any incomplete* series with:
    - 3 PCV13 doses: 1 dose PCV13 (at least 8 weeks after any prior PCV13 dose)
    - Less than 3 PCV13 doses: 2 doses PCV13 (8 weeks after the most recent dose and administered 8 weeks apart)
  - No history of PPSV23: 1 dose PPSV23 (at least 8 weeks after any prior PCV13 dose) and a 2nd dose of PPSV23 5 years later
- Age 6–18 years
  - No history of either PCV13 or PPSV23: 1 dose PCV13, 2 doses PPSV23 (dose 1 of PPSV23 administered 8 weeks after PCV13 and dose 2 of PPSV23 administered at least 5 years after dose 1 of PPSV23)
  - Any PCV13 but no PPSV23: 2 doses PPSV23 (dose 1 of PPSV23 administered 8 weeks after the most recent dose of PCV13 and dose 2 of PPSV23 administered at least 5 years after dose 1 of PPSV23)
  - PPSV23 but no PCV13: 1 dose PCV13 at least 8 weeks after the most recent PPSV23 dose and a 2nd dose of PPSV23 administered 5 years after dose 1 of PPSV23 and at least 8 weeks after a dose of PCV13
Chronic liver disease, alcoholism:
- Age 6–18 years
  - No history of PPSV23: 1 dose PPSV23 (at least 8 weeks after any prior PCV13 dose)

*Incomplete series = Not having received all doses in either the recommended series or an age-appropriate catch-up series.

Poliovirus vaccination

Minimum age: 6 weeks

Routine vaccination

4-dose series at ages 2, 4, 6–18 months, 4–6 years; administer the final dose at or after age 4 years and at least 6 months after the previous dose.
4 or more doses of IPV can be administered before age 4 years when a combination vaccine containing IPV is used. However, a dose is still recommended at or after age 4 years and at least 6 months after the previous dose.

Catch-up vaccination

In the first 6 months of life, use minimum ages and intervals only for travel to a polio-endemic region or during an outbreak.
IPV is not routinely recommended for U.S. residents 18 years and older.

Series containing oral polio vaccine (OPV), either mixed OPV-IPV or OPV-only series:

Total number of doses needed to complete the series is the same as that recommended for the U.S. IPV schedule.
Only trivalent OPV (tOPV) counts toward the U.S. vaccination requirements.
- Doses of OPV administered before April 1, 2016, should be counted (unless specifically noted as administered during a campaign).
- Doses of OPV administered on or after April 1, 2016, should not be counted.
For other catch-up guidance, see Tables 4 and 5.

Rotavirus vaccination

Minimum age: 6 weeks

Routine vaccination

Rotarix: 2-dose series at 2 and 4 months
RotaTeq: 3-dose series at 2, 4, and 6 months
If any dose in the series is either RotaTeq or unknown, default to 3-dose series.

Catch-up vaccination

Do not start the series on or after age 15 weeks, 0 days.
The maximum age for the final dose is 8 months, 0 days.
For other catch-up guidance, see Tables 4 and 5.

Tetanus, diphtheria, and pertussis (Tdap) vaccination

Minimum age: 11 years for routine vaccination, 7 years for catch-up vaccination

Routine vaccination

Adolescents age 11–12 years: 1 dose Tdap
Pregnancy: 1 dose Tdap during each pregnancy, preferably in early part of gestational weeks 27–36
Tdap may be administered regardless of the interval since the last tetanus- and diphtheria-toxoid-containing vaccine.

Catch-up vaccination

Adolescents age 13–18 years who have not received Tdap: 1 dose Tdap, then Td or Tdap booster every 10 years
Persons age 7–18 years not fully vaccinated* with DTaP: 1 dose Tdap as part of the catch-up series (preferably the first dose); if additional doses are needed, use Td or Tdap.
Tdap administered at 7–10 years
- Children age 7–9 years who receive Tdap should receive the routine Tdap dose at age 11–12 years.
- Children age 10 years who receive Tdap do not need to receive the routine Tdap dose at age 11–12 years.
DTaP inadvertently administered at or after age 7 years:
- Children age 7–9 years: DTaP may count as part of catch-up series. Routine Tdap dose at age 11–12 years should be administered.
- Children age 10–18 years: Count dose of DTaP as the adolescent Tdap booster.
For other catch-up guidance, see Tables 4 and 5.

*Fully vaccinated = 5 valid doses of DTaP OR 4 valid doses of DTaP if dose 4 was administered at age 4 years or older.

Varicella vaccination

Minimum age: 12 months

Routine vaccination

2-dose series at 12–15 months, 4–6 years
Dose 2 may be administered as early as 3 months after dose 1 (a dose administered after a 4-week interval may be counted).

Catch-up vaccination

Ensure persons age 7–18 years without evidence of immunity have 2-dose series:
- Age 7–12 years: routine interval: 3 months (a dose administered after a 4-week interval may be counted)
- Age 13 years and older: routine interval: 4–8 weeks (minimum interval: 4 weeks)
- The maximum age for use of MMRV is 12 years.

Vaccine ingredients sorted by vaccine

Vaccines contain ingredients, called antigens, which cause the body to develop immunity. Vaccines also contain very small amounts of other ingredients. All ingredients either help make the vaccine, or ensure the vaccine is safe and effective. These types of ingredients are listed below.

Table 8. Vaccine ingredients

Type of Ingredient	Examples	Purpose
Preservatives	Thimerosal (only in multi-dose vials of flu vaccine)*	To prevent contamination
Adjuvants	Aluminum salts	To help stimulate the body’s response to the antigens
Stabilizers	Sugars, gelatin	To keep the vaccine potent during transportation and storage
Residual cell culture materials	Egg protein	To grow enough of the virus or bacteria to make the vaccine
Residual inactivating ingredients	Formaldehyde	To kill viruses or inactivate toxins during the manufacturing process
Residual antibiotics	Neomycin	To prevent contamination by bacteria during the vaccine manufacturing process

Footnote: *Today, the only childhood vaccines used routinely in the United States that contain thimerosal (mercury) are flu vaccines in multi-dose vials. These vials have very tiny amounts of thimerosal as a preservative. This is necessary because each time an individual dose is drawn from a multi-dose vial with a new needle and syringe, there is the potential to contaminate the vial with harmful microbes (toxins).

[Source ⁶ ]

Additional Facts

Additives used in the production of vaccines may include:

suspending fluid (e.g. sterile water, saline, or fluids containing protein);
preservatives and stabilizers to help the vaccine remain unchanged (e.g. albumin, phenols, and glycine); and
adjuvants or enhancers to help the vaccine to be more effective.

Common substances found in vaccines include ⁶:

Aluminum gels or salts of aluminum which are added as adjuvants to help the vaccine stimulate a better response. Adjuvants help promote an earlier, more potent response, and more persistent immune response to the vaccine.
Antibiotics which are added to some vaccines to prevent the growth of germs (bacteria) during production and storage of the vaccine. No vaccine produced in the United States contains penicillin.
Egg protein is found in influenza and yellow fever vaccines, which are prepared using chicken eggs. Ordinarily, persons who are able to eat eggs or egg products safely can receive these vaccines.
Formaldehyde is used to inactivate bacterial products for toxoid vaccines, (these are vaccines that use an inactive bacterial toxin to produce immunity.) It is also used to kill unwanted viruses and bacteria that might contaminate the vaccine during production. Most formaldehyde is removed from the vaccine before it is packaged.
Monosodium glutamate (MSG) and 2-phenoxy-ethanol which are used as stabilizers in a few vaccines to help the vaccine remain unchanged when the vaccine is exposed to heat, light, acidity, or humidity.
Thimerosal is a mercury-containing preservative that is added to vials of vaccine that contain more than one dose to prevent contamination and growth of potentially harmful bacteria.

For children with a prior history of allergic reactions to any of these substances in vaccines, parents should consult their child’s healthcare provider before vaccination.

Thimerosal, Mercury, and Vaccine Safety

Thimerosal is a compound that contains mercury ⁷. Mercury is a metal found naturally in the environment. Thimerosal is used as a preservative in multi-dose vials of flu vaccines, and in two other childhood vaccines, it is used in the manufacturing process. When each new needle is inserted into the multi-dose vial, it is possible for microbes to get into the vial. The preservative, thimerosal, prevents contamination in the multi-dose vial when individual doses are drawn from it. Receiving a vaccine contaminated with bacteria can be deadly.

There is no evidence that the small amounts of thimerosal in flu vaccines cause any harm, except for minor reactions like redness and swelling at the injection site. Although no evidence suggests that there are safety concerns with thimerosal, vaccine manufacturers have stopped using it as a precautionary measure. Flu vaccines that do not contain thimerosal are available (in single dose vials).

Today, no childhood vaccine used in the U.S.—except some formulations of flu vaccine in multi-dose vials—use thimerosal as a preservative.

Was thimerosal in vaccines a cause of autism?

Reputable scientific studies have shown that mercury in vaccines given to young children is not a cause of autism. The studies used different methods. Some examined rates of autism in a state or a country, comparing autism rates before and after thimerosal was removed as a preservative from vaccines. In the United States and other countries, the number of children diagnosed with autism has not gone down since thimerosal was removed from vaccines.

What keeps today’s childhood vaccines from becoming contaminated if they do not contain thimerosal as a preservative?

The childhood vaccines that used to contain thimerosal as a preservative are now put into single-dose vials, so no preservative is needed. In the past, the vaccines were put into multi-dose vials, which could become contaminated when new needles were used to get vaccine out of the vial for each dose.

Vaccine side effects and risks

Like any medication, vaccines can cause side effects. The most common side effects are mild. On the other hand, many vaccine-preventable disease symptoms can be serious, or even deadly. Even though many of these diseases are rare in this country, they still occur around the world. Unvaccinated U.S. citizens who travel abroad can bring these diseases to the U.S., putting unvaccinated children at risk.

The side effects from vaccines are almost always minor (such as redness and swelling where the shot was given) and go away within a few days. If your child experiences a reaction at the injection site, use a cool, wet cloth to reduce redness, soreness, and swelling.

Serious side effects after vaccination, such as severe allergic reaction, are very rare and doctors and clinic staff are trained to deal with them. Pay extra attention to your child for a few days after vaccination. If you see something that concerns you, call your child’s doctor.

Immunization vs Vaccination

The terms ‘vaccination’ and ‘immunization’ don’t mean quite the same thing. Vaccination is the term used for getting a vaccine, that is, actually getting the injection or taking an oral vaccine dose. Immunization refers to the process of both getting the vaccine and becoming immune to the disease following vaccination. Vaccines train your immune system to quickly recognize and clear out germs (bacteria and viruses) that can cause serious illnesses. Vaccines strengthen your immune system a bit like exercise strengthens muscles.

How does immunization work?

All forms of immunization work in the same way. When someone is injected with a vaccine, their body produces an immune response in the same way it would following exposure to a disease but without the person getting the disease. If the person comes in contact with the disease in the future, the body is able to make an immune response fast enough to prevent the person developing the disease or developing a severe case of the disease.

Vaccines are a safe and clever way of producing an immune response in the body without causing illness.

Vaccines use dead or severely weakened viruses to trick your body into thinking you have already had the disease.

When you get a vaccine, your immune system responds to these weakened ‘invaders’ and creates antibodies to protect you against future infection. It has special ‘memory’ cells that remember and recognize specific germs or viruses.

Vaccines strengthen your immune system by training it to recognize and fight against specific germs.

When you come across that virus in the future, your immune system rapidly produces antibodies to destroy it. In some cases, you may still get a less serious form of the illness, but you are protected from the most dangerous effects.

How does the immune system works?

Every day you come into contact with germs, including bacteria and viruses. A healthy immune system stops you getting sick from these germs.

The immune response is the way your body defends itself. It recognizes harmful bacteria, viruses and any other substances, also known as antigens, when they enter your body.

When an antigen like the cold virus enters your body, your immune response first produces something called mucus. The mucus tries to flush out the virus and stop more of it from entering the body.

Next, your immune response can send white blood cells to surround the virus to prevent more harm.

Lastly, it can produce special cells called antibodies. Antibodies can lock onto and destroy the virus.

The immune system is at work all the time to keep you as healthy as possible.

How Vaccines Prevent Diseases

The diseases vaccines prevent can be dangerous, or even deadly. Vaccines reduce your or your child’s risk of infection by working with your or your child body’s natural defenses to help them safely develop immunity to disease.

When germs, such as bacteria or viruses, invade the body, they attack and multiply. This invasion is called an infection, and the infection is what causes illness. The immune system then has to fight the infection. Once it fights off the infection, the body has a supply of cells that help recognize and fight that disease in the future. These supplies of cells are called antibodies.

Vaccines help develop immunity by imitating an infection, but this “imitation” infection does not cause illness. Instead it causes the immune system to develop the same response as it does to a real infection so the body can recognize and fight the vaccine-preventable disease in the future. Sometimes, after getting a vaccine, the imitation infection can cause minor symptoms, such as fever. Such minor symptoms are normal and should be expected as the body builds immunity.

As children get older, they require additional doses of some vaccines for best protection. Older kids also need protection against additional diseases they may encounter.

What if we stopped vaccinating?

So what would happen if we stopped vaccinating here? Diseases that are almost unknown would stage a comeback. Before long you would see epidemics of diseases that are nearly under control today. More children would get sick and more would die.

In 1974, Japan had a successful pertussis (whooping cough) vaccination program, with nearly 80% of Japanese children vaccinated. That year only 393 cases of pertussis were reported in the entire country, and there were no deaths from pertussis. But then rumors began to spread that pertussis vaccination was no longer needed and that the vaccine was not safe, and by 1976 only 10% of infants were getting vaccinated. In 1979 Japan suffered a major pertussis epidemic, with more than 13,000 cases of whooping cough and 41 deaths. In 1981 the government began vaccinating with acellular pertussis vaccine, and the number of pertussis cases dropped again.

Why get immunization?

As a parent, you may get upset or concerned when you watch your baby get 3 or 4 shots during a doctor’s visit. But, all of those shots add up to protection for your baby against 14 infectious diseases. Young babies can get very ill from vaccine-preventable diseases.

Immunization is a safe and effective way to protect you and your children from harmful, contagious diseases. Immunization also safeguards the health of other people, now and for future generations.

The Advisory Committee on Immunization Practices ⁸, a group of medical and public health experts that develops recommendations on how to use vaccines to control diseases in the United States, designs the vaccination schedule. The Advisory Committee on Immunization Practices ⁸ designs the vaccination schedule to protect young children before they are likely to be exposed to potentially serious diseases and when they are most vulnerable to serious infections.

Although children continue to get several vaccines up to their second birthday, these vaccines do not overload the immune system. Every day, your healthy baby’s immune system successfully fights off thousands of antigens – the parts of germs that cause their immune system to respond. The antigens in vaccines come from weakened or killed germs so they cannot cause serious illness. Even if your child receives several vaccines in one day, vaccines contain only a tiny amount of antigens compared to the antigens your baby encounters every day.

This is the case even if your child receives combination vaccines. Combination vaccines take two or more vaccines that could be given individually and put them into one shot. Children get the same protection as they do from individual vaccines given separately—but with fewer shots.

Before vaccination campaigns in the 1960s and 1970s, diseases like tetanus, diphtheria, and whooping cough killed thousands of children. Today, it is extremely rare to die from these diseases in America.

When you get immunized, you protect yourself as well as helping to protect the whole community. When enough people in the community get immunized, it is more difficult for these diseases to spread. This helps to protect people who are at more risk of getting the disease, including unvaccinated members of the community. This means that even those who are too young or too sick to be vaccinated will not encounter the disease. Scientists call this ‘herd immunity’ and it can save lives.

If enough people in the community get immunized against a disease, the infection can no longer spread from person to person. The disease can die out altogether. For example, smallpox was eradicated in 1980 after a vaccination campaign led by the World Health Organization.

A similar campaign by the Global Polio Eradication Initiative has succeeded in reducing the number of polio cases. There are now only a few cases remaining in the developing world today.

Is ‘natural’ immunization better?

If a disease infects you, then you may become immune to it in the future. Doctors call this ‘natural’ immunity.

Some people believe that natural immunity is better than the immunity from vaccines. But the risks associated with natural immunity are much higher than risks associated with immunity provided by vaccines. Some highly contagious diseases can lead to severe complications. They can make you very ill or even kill you.

The benefits of vaccination far outweigh the risks. Vaccination protects you and your family from diseases, including ones that are deadly. It also protects other people in your community, including people who are vulnerable, too young, or too sick to be immunized.

The estimation is that immunization programs prevent about 2.5 million deaths every year.

Vaccination also helps protect the health of future generations, for example against the crippling disease polio.

Isn’t it better for children to develop immunity from the disease?

Allowing children to develop immunity by catching the diseases is not safe. Although catching a vaccine-preventable disease often protects a child from catching it again, it can make them seriously ill in the process. In comparison, vaccines are designed so that they can stimulate immunity but without causing disease. The side effects of vaccination are usually mild (like getting a sore arm) and pass quickly but the diseases they prevent can cause serious illnesses requiring hospital treatment. Occasionally children still die in United States from vaccine-preventable diseases. Vaccination is recommended because it is the safest way to develop immunity.

What are the risks and benefits of vaccines?

Vaccines can prevent infectious diseases that once killed or harmed many infants, children, and adults. Without vaccines, your child is at risk for getting seriously ill and suffering pain, disability, and even death from diseases like measles and whooping cough. The main risks associated with getting vaccines are side effects, which are almost always mild (redness and swelling at the injection site) and go away within a few days. Serious side effects after vaccination, such as a severe allergic reaction, are very rare and doctors and clinic staff are trained to deal with them. The disease-prevention benefits of getting vaccines are much greater than the possible side effects for almost all children. The only exceptions to this are cases in which a child has a serious chronic medical condition like cancer or a disease that weakens the immune system, or has had a severe allergic reaction to a previous vaccine dose.

How long do immunizations take to work?

In general, the normal immune response takes approximately 2 weeks to work. This means protection from an infection will not occur immediately after immunization. Most immunizations need to be given several times to build long-lasting protection.

A child who has been given only one or two doses of diphtheria-tetanus-acellular pertussis vaccine (DTPa) is only partially protected against diphtheria, tetanus and pertussis (whooping cough), and may become sick if exposed to these diseases. However, some of the new vaccines, such as the meningococcal C vaccine, provide long-lasting immunity after only one dose.

How long do immunizations last?

The protective effect of immunizations is not always lifelong. Some, like tetanus vaccine, can last up to 30 years, after which time a booster dose may be given. Some immunizations, such as whooping cough vaccine, give protection for about 5 years after a full course. Influenza immunization is needed annually due to frequent changes to the type of flu virus in the community.

Is everyone protected from disease by immunization?

Even when all the doses of a vaccine have been given, not everyone is protected against the disease. Measles, mumps, rubella, tetanus, polio, hepatitis B and Hib vaccines protect more than 95% of children who have completed the course. One dose of meningococcal C vaccine at 12 months protects over 90% of children.

Three doses of whooping cough vaccine protects about 85% of children who have been immunized, and will reduce the severity of the disease in the other 15%, if they do catch whooping cough. Booster doses are needed because immunity decreases over time.

What is in vaccines?

Some vaccines contain a very small dose of a live, but weakened form of a virus. Some vaccines contain a very small dose of killed bacteria or small parts of bacteria, and other vaccines contain a small dose of a modified toxin produced by bacteria.

Vaccines may also contain either a small amount of preservative or a small amount of an antibiotic to preserve the vaccine. Some vaccines may also contain a small amount of an aluminium salt which helps produce a better immune response.

Is there a link between vaccines and autism?

No. Scientific studies and reviews continue to show no relationship between vaccines and autism.

Some people have suggested that thimerosal (a compound that contains mercury) in vaccines given to infants and young children might be a cause of autism. Others have suggested that the MMR (measles- mumps-rubella) vaccine may be linked to autism. However, numerous scientists and researchers have studied and continue to study the MMR vaccine and thimerosal, and reach the same conclusion: there is no link between MMR vaccine or thimerosal and autism.

Can vaccines overwhelm my baby’s immune system?

Vaccines cannot overwhelm a baby’s immune system. From the moment they are born babies are exposed to countless germs (bacteria and viruses) every day through their skin, noses, throats and guts. Babies’ immune systems are designed to deal with this constant exposure to new things, learning to recognize and respond to things that are harmful. Even if all the vaccine doses on the schedule were given to a baby all at once, only a small fraction of available immune cells
would be occupied. The immune system is still able to respond to all other threats at any time.

Don’t infants have natural immunity? Isn’t natural immunity better than the kind from vaccines?

Babies may get some temporary immunity (protection) from mom during the last few weeks of pregnancy, but only for diseases to which mom is immune. Breastfeeding may also protect your baby temporarily from minor infections, like colds. These antibodies do not last long, leaving your baby vulnerable to disease.

Natural immunity occurs when your child is exposed to a disease and becomes infected. It is true that natural immunity usually results in better immunity than vaccination, but the risks are much greater. A natural chickenpox infection may result in pneumonia, whereas the vaccine might only cause a sore arm for a couple of days.

Wouldn’t it be safer to vaccinate babies when they are older?

Vaccines are given as soon as it is safe to give them. Babies and young children are most vulnerable to infections when they are very young. In order to protect babies from diseases, they need to be vaccinated before they come into contact with the diseases. Delaying vaccination would leave babies and young children in danger of catching diseases for longer. Babies need the protection vaccines can give them as soon as possible.

Why are so many doses needed for each vaccine?

Getting every recommended dose of each vaccine provides your child with the best protection possible. Depending on the vaccine, your child will need more than one dose to build high enough immunity to prevent disease or to boost immunity that fades over time. Your child may also receive more than one dose to make sure they are protected if they did not get immunity from a first dose, or to protect them against germs that change over time, like flu. Every dose is important because each protects against infectious diseases that can be especially serious for infants and very young children.

Why do vaccines start so early?

The recommended schedule protects infants and children by providing immunity early in life, before they come into contact with life-threatening diseases. Children receive immunization early because they are susceptible to diseases at a young age. The consequences of these diseases can be very serious, even life-threatening, for infants and young children.

What do you think of delaying some vaccines or following a non-standard schedule?

Children do not receive any known benefits from following schedules that delay vaccines. Infants and young children who follow immunization schedules that spread out or leave out shots are at risk of developing diseases during the time you delay their shots. Some vaccine-preventable diseases remain common in the United States and children may be exposed to these diseases during the time they are not protected by vaccines, placing them at risk for a serious case of the disease that might cause hospitalization or death.

Can’t I just wait to vaccinate my baby, since he isn’t in child care, where he could be exposed to diseases?

No, even young children who are cared for at home can be exposed to vaccine preventable diseases, so it’s important for them to get all their vaccines at the recommended ages. Children can catch these illnesses from any number of people or places, including from parents, brothers or sisters, visitors to their home, on playgrounds or even at the grocery store. Regardless of whether or not your baby is cared for outside the home, she comes in contact with people throughout the day, some of whom may be sick but not know it yet.

If someone has a vaccine preventable disease, they may not have symptoms or the symptoms may be mild, and they can end up spreading disease to babies or young children. Remember, many of these diseases can be especially dangerous to young children so it is safest to vaccinate your child at the recommended ages to protect her, whether or not she is in child care.

Can’t I just wait until my child goes to school to catch up on immunizations?

Before entering school, young children can be exposed to vaccine-preventable diseases from parents and other adults, brothers and sisters, on a plane, at child care, or even at the grocery store. Children under age 5 are especially susceptible to diseases because their immune systems have not built up the necessary defenses to fight infection. Don’t wait to protect your baby and risk getting these diseases when he or she needs protection now.

What’s wrong with delaying some of my baby’s vaccines if I’m planning to get them all eventually?

Young children have the highest risk of having a serious case of disease that could cause hospitalization or death. Delaying or spreading out vaccine doses leaves your child unprotected during the time when they need vaccine protection the most. For example, diseases such as Hib or pneumococcus almost always occur in the first 2 years of a baby’s life. And some diseases, like Hepatitis B and whooping cough (pertussis), are more serious when babies get them at a younger age. Vaccinating your child according to the CDC’s recommended immunization schedule means you can help protect him at a young age.

I got the whooping cough and flu vaccines during my pregnancy. Why does my baby need these vaccines too?

The protection (antibodies) you passed to your baby before birth will give him some early protection against whooping cough and flu. However, these antibodies will only give him short-term protection. It is very important for your baby to get vaccines on time so he can start building his own protection against these serious diseases.

Do I have to vaccinate my baby on schedule if I’m breastfeeding him?

Yes, even breastfed babies need to be protected with vaccines at the recommended ages. The immune system is not fully developed at birth, which puts newborns at greater risk for infections.

Breast milk provides important protection from some infections as your baby’s immune system is developing. For example, babies who are breastfed have a lower risk of ear infections, respiratory tract infections, and diarrhea. However, breast milk does not protect children against all diseases. Even in breastfed infants, vaccines are the most effective way to prevent many diseases. Your baby needs the long-term protection that can only come from making sure he receives all his vaccines according to the CDC’s recommended schedule.

Should I get vaccinated if I have allergies?

This depends on the allergy you have. Always ask for medical advice to determine whether you can safely receive vaccinations.

What if I or my child are egg-sensitive?

A number of studies show that most people with anaphylaxis or allergy to eggs can be safely vaccinated.

If you are unsure, ask your doctor.

What if I have a reaction after receiving a vaccination?

It is important to report negative reactions to a vaccination. This gives us a better understanding of the safety of vaccines.

You can report adverse events to the Vaccine Adverse Event Reporting System (VAERS) at https://vaers.hhs.gov/

In general, most children who have had a reaction to a vaccination can be safely re-vaccinated. Immunization specialist services are available in some states. They can advise whether your child needs more testing or precautions before receiving further vaccines. Contact your state or territory health department for details about these services.

What if a family member has had a reaction to an immunization?

Adverse reactions are not hereditary. You should not avoid immunizations because another family member has had a reaction to a vaccine.

What are combination vaccines? Why are they used?

Combination vaccines protect your child against more than one disease with a single shot. They reduce the number of shots and office visits your child would need, which not only saves you time and money, but also is easier on your child.

Some common combination vaccines are Pediarix® which combines DTap, Hep B, and IPV (polio) and ProQuad® which combines MMR and varicella (chickenpox).

Why does my child need a chickenpox shot? Isn’t it a mild disease?

Your child needs a chickenpox vaccine because chickenpox can actually be a serious disease. In many cases, children experience a mild case of chickenpox, but other children may have blisters that become infected. Others may develop pneumonia. There is no way to tell in advance how severe your child’s symptoms will be.

Before vaccine was available, about 50 children died every year from chickenpox, and about 1 in 500 children who got chickenpox was hospitalized.

Who can be immunized?

Most people can be immunized, except for people with certain medical conditions and people who are severely allergic (anaphylactic) to vaccine ingredients.

Certain medical conditions may influence whether you can be immunized. Your ability to be immunized may change when your condition changes.

You should consult your doctor before immunization if you:

have a fever of more than 101.3 °F (38.5 °C) on the day of your vaccination
are receiving a medical treatment such as chemotherapy
have had a bad reaction to a vaccine in the past
are planning pregnancy, are pregnant or breastfeeding
are an organ transplant recipient
have an autoimmune disease or chronic condition.

When do I get immunized?

Your health, age, lifestyle and job will determine the vaccines you need and when to get them.

Health: Some health conditions may make you more vulnerable to vaccine-preventable diseases. For example, babies born prematurely, or people who have a weakened immune system may benefit from additional or more frequent immunizations.
Age: People need protection from different diseases at different ages.
Lifestyle: Lifestyle choices can have an impact on your immunization needs. You may benefit from immunizations if you are traveling overseas, planning a family, sexually active, a smoker or play sport that may expose you to someone’s blood.
Occupation: Some jobs may expose you to a greater risk of contact with vaccine-preventable diseases or put you in contact with people who are more susceptible to vaccine-preventable diseases. This includes people working in aged care, childcare, healthcare or emergency service. Find out more about immunization for work.

Vaccines During Pregnancy

Even before becoming pregnant, make sure you are up to date on all your vaccines. This will help protect you and your child from serious diseases. You probably know that when you are pregnant, you share everything with your baby. That means when you get vaccines, you aren’t just protecting yourself—you are giving your baby some early protection too. For example, rubella is a contagious disease that can be very dangerous if you get it while you are pregnant. In fact, it can cause a miscarriage or serious birth defects. The best protection against rubella is MMR (measles-mumps-rubella) vaccine, but if you aren’t up to date, you’ll need it before you get pregnant. Make sure you have a pre-pregnancy blood test to see if you are immune to the disease. Most women were vaccinated as children with the MMR vaccine, but you should confirm this with your doctor. If you need to get vaccinated for rubella, you should avoid becoming pregnant until one month after receiving the MMR vaccine and, ideally, not until your immunity is confirmed by a blood test. The Centers for Disease Control and Prevention (CDC) recommends you get a whooping cough and flu vaccine during each pregnancy to help protect yourself and your baby ⁹.

Vaccines for Travel: If you are pregnant and planning international travel, you should talk to your doctor at least 4 to 6 weeks before your trip to discuss any special precautions or vaccines that you may need.

Hepatitis B: A baby whose mother has hepatitis B is at highest risk for becoming infected with hepatitis B during delivery. Talk to your healthcare professional about getting tested for hepatitis B and whether or not you should get vaccinated.

Additional Vaccines: Some women may need other vaccines before, during, or after they become pregnant. For example, if you have a history of chronic liver disease, your doctor may recommend the hepatitis A vaccine. If you work in a lab, or if you are traveling to a country where you may be exposed to meningococcal disease, your doctor may recommend the meningococcal vaccine.

Vaccinations before pregnancy

Measles, mumps and rubella

Rubella infection during pregnancy can cause serious birth defects. If you were born after 1966, you may need a booster vaccination for full protection. This should be done in consultation with your doctor. It is recommended that you wait four weeks after receiving this vaccine before trying to get pregnant.

Chickenpox (varicella)

Chickenpox infection during pregnancy can cause severe illness in you and your unborn baby. A simple blood test can determine if you have immunity to this infection. If you are not protected, speak to your doctor about receiving two doses of the vaccine for full immunity. It is recommended that you wait four weeks after receiving this vaccine before trying to get pregnant.

Pneumococcal

Protection against serious illness caused by pneumococcal disease is recommended for smokers and people with chronic heart, lung or kidney disease, or diabetes.

Travel vaccinations

Vaccines that are required to travel to other countries are not always recommended during pregnancy. Find out more about travel and pregnancy.

Safe vaccinations during pregnancy

Influenza and pertussis vaccines are the only vaccines recommended for women during pregnancy.

Whooping cough (pertussis)

Whooping cough (pertussis) can cause serious illness for anyone and even death in babies less than six months old. Up to 20 babies die each year in the United States due to whooping cough. About half of babies younger than 1 year old who get whooping cough need treatment in the hospital. The younger the baby is when he or she gets whooping cough, the more likely he or she will need to be treated in a hospital. It may be hard for you to know if your baby has whooping cough because many babies with this disease don’t cough at all. Instead, it can cause them to stop breathing and turn blue.

It is now recommended that all pregnant women receive a pertussis (whooping cough) vaccination during their third trimester (ideally at 28 weeks). A combination of antibodies being passed through the mother’s bloodstream to your baby before birth and the reduced risk of the mother contracting the disease makes this an ideal time to administer the vaccine. These antibodies will provide your baby some short-term, early protection against whooping cough. Most states now offer the pertussis vaccination for free. Speak to your doctor or antenatal care provider to schedule an appointment.

You should get the Tdap vaccine (to help protect against whooping cough), during your pregnancy.

Flu (influenza)

Influenza can cause serious illness and being pregnant increases the risk of flu complications, with the risk to pregnant women of serious complications up to five times higher than normal. Catching the flu also increases your chances for serious problems for your developing baby, including premature labor and delivery. Get the flu shot if you are pregnant during flu season—it’s the best way to protect yourself and your baby for several months after birth from flu-related complications. Because of this, the flu vaccine is recommended and funded for all pregnant women.

The influenza vaccine is safe and can be administered before, during or after pregnancy. Getting vaccinated every year protects you against new strains of the virus and also reduces the risk of spreading influenza to your baby, who are also at higher risk of complications if they do get flu. Getting the flu vaccine during your pregnancy will also provide ongoing protection to your newborn for the first 6 months after birth.

Flu seasons vary in their timing from season to season, but CDC recommends getting vaccinated with the flu shot by the end of October, if possible. This timing helps protect you before flu activity begins to increase.

Who cannot be immunized?

The only people who cannot ever be immunized are people who have had severe allergic reactions (anaphylaxis) to vaccines ingredients which is rare.

In general, people that should not receive live vaccines include:

people who are significantly immunocompromised, for example people undergoing a treatment that suppresses the immune system, such as chemotherapy
pregnant women.

Check with your doctor before vaccination if you or your child falls into any of the groups above.

Immunization Schedule for Adults (19 Years of Age and Older)

Table 9. Recommended Immunization Schedule for Adults 19 Years of Age and Older, United States 2022

Footnotes: YELLOW = Recommended vaccination for adults who meet age requirement, lack documentation of vaccination, or lack evidence of past infection; PURPLE = Recommended vaccination for adults with an additional risk factor or another indication; BLUE = Recommended vaccination based on shared clinical decision-making; GREY = No recommendation/Not applicable

If you are traveling outside the United States, you may need additional vaccines. Ask your health care professional about which vaccines you may need at least 6 weeks before you travel.

[Source ¹⁰ ]

Immunization Records

Keeping up-to-date immunization records for your family, especially your children, is important. You will need your children’s immunization records to register them for school, child care, athletic teams, and summer camps or to travel.

Good record-keeping begins with good record-taking. When you need official copies of immunizations records to enroll your child in child care, school, and summer camps or for international travel, they will be much easier to get if you have accurate, up-to-date personal records.

You can get an immunization tracking card from your child’s doctor or from your state health department to keep record of your child’s vaccines. Or, you can use the Centers for Disease Control and Prevention’s Immunization Tracker to record your children’s immunizations, developmental milestones, and growth from birth through 6 years old. You can also ask your doctor to record the vaccines your child has received in your state’s immunization registry.

Table 10. Centers for Disease Control and Prevention’s Immunization Tracker

How to get immunization records

The Centers for Disease Control and Prevention (CDC) does not have immunization record information. If you need official copies of immunization records for your child or to update your personal records, there are several places you can look:

Check with your child’s doctor or public health clinic. However, doctor’s offices and clinics may only keep immunization records for a few years.
Check with your state’s health department. You can:
- Request a copy of your child’s immunization record.
- Ask if your child’s immunization record is in an immunization registry, or Immunization Information System (IIS). An Immunization Information System (IIS) is a computer system your doctor or public health clinic may use to keep track of immunizations your child has received. Most states have an IIS; contact the Immunization Information System (IIS) in the state where your child received their last shots to see if records exist. Find Your Child’s Immunization Record through Your State’s Immunization Information System (IIS) here https://www.cdc.gov/vaccines/programs/iis/contacts-locate-records.html#state
Check with your child’s school. Some schools keep on file the immunization records of children who attended. However, schools generally keep these records for only a year or two after the student graduates, transfers to another school, or leaves the school system. After a student leaves the school system, schools send records to storage and they may not be able to access them unless they are stored in an Immunization Information System (IIS).
Check with college medical or student health services for your college-age child. Many colleges provide vaccinations, especially those required for enrollment. Contact your college’s medical services or student health department for further information.

You can go to the Immunization Action Coalition’s site for more tips on locating old immunization records – http://www.vaccineinformation.org/finding-vaccine-records/

Immunization Records for Adoption and Foster Care

You should ask your adoption coordinator for your child’s immunization records so that you can confirm which vaccinations the child has already received. An internationally adopted child should be considered susceptible to disease and should be vaccinated (or revaccinated) against vaccine-preventable diseases if vaccination records are:

lost,
incomplete,
difficult to understand, or
if you or your child’s doctor thinks they are inaccurate.

Foster Children

Each state’s Child Welfare Agency has different policies about immunizing foster children. However, in most cases, as a foster parent, you need to get consent for emergency and routine medical care for your foster child. You should talk to your child’s caseworker or the agency that placed your child with you about getting consent. Once you have permission, you should ask your child’s caseworker for any available medical records. You can use these records to figure out whether or not your foster child is behind in any immunization. If your child is not up-to-date on their immunizations, you should make an appointment with a doctor. As a foster parent, you should keep records of all vaccinations a foster child receives under your care.

Domestic Adoption

When adopting a child domestically, you should ask your adoption coordinator for your child’s official immunization records. If the records are not available, you may have to search for the records.

For tips on locating your child’s vaccination record, see Finding Official Immunization Records here https://www.cdc.gov/vaccines/programs/iis/contacts-locate-records.html#state

You can also contact your state immunization program for more information about places to find your child’s vaccination records here https://www.cdc.gov/vaccines/imz-managers/awardee-imz-websites.html

If you are unable to locate your child’s immunization records, medical experts recommend vaccinating. Your child may be left vulnerable to vaccine-preventable diseases if you are not certain about the vaccinations that your child has received. It is safe for your child to be vaccinated, even if they may have already received that vaccine. Vaccinating is the best way to ensure protection.

International Adoption

Vaccinate according to the U.S. schedule

All international adoptees should receive vaccines according to the U.S. Childhood Immunization Schedule. In addition, a child’s birth country may have vaccines or a vaccination schedule that is different from the recommended immunization schedule in the United States.

What To Do If You Can’t Find Your Child’s Immunization Records

If you cannot find your child’s vaccination records through your doctor or health department or their records are incomplete, your child should be considered susceptible to disease and should be vaccinated (or revaccinated). Children can have their blood tested for antibodies to determine their immunity to certain diseases. However, these tests may not always be accurate, so the doctor may not be sure your child is truly protected. In some cases, doctors may prefer to revaccinate your child for best protection. It is safe for your child to receive a vaccine, even if they may have already received it. Talk to your child’s doctor to determine what vaccines your child needs for protection against vaccine preventable diseases.

References

Immunization Schedules. https://www.cdc.gov/vaccines/schedules/easy-to-read/child-easyread.html
Recommended Child and Adolescent Immunization Schedule for ages 18 years or younger, United States, 2022. https://www.cdc.gov/vaccines/schedules/hcp/imz/child-adolescent.html
Catch-up Immunization Schedule for Children and Adolescents Who Start Late or Who Are More than 1 Month Behind. Recommendations for Ages 18 Years or Younger, United States, 2022. https://www.cdc.gov/vaccines/schedules/hcp/imz/catchup.html
List of Vaccines Used in United States. https://www.cdc.gov/vaccines/vpd/vaccines-list.html
Recommended Child and Adolescent Immunization Schedule for ages 18 years or younger, United States, 2020. https://www.cdc.gov/vaccines/schedules/hcp/imz/child-adolescent.html
Ingredients of Vaccines – Fact Sheet. https://www.cdc.gov/vaccines/vac-gen/additives.htm
Understanding Thimerosal, Mercury, and Vaccine Safety. https://www.cdc.gov/vaccines/hcp/conversations/downloads/vacsafe-thimerosal-color-office.pdf
Advisory Committee on Immunization Practices (ACIP). https://www.cdc.gov/vaccines/acip/index.html
Pregnancy and Vaccination. https://www.cdc.gov/vaccines/pregnancy/pregnant-women/index.html
Adult Immunization Schedule. Recommendations for Ages 19 Years or Older, United States, 2022. https://www.cdc.gov/vaccines/schedules/hcp/imz/adult.html

Vaccines and Vaccinations

Vaccines are injections (shots), liquids, pills, or nasal sprays that you take to teach your body’s immune system to recognize and defend against harmful germs. When someone is injected with a vaccine, their body produces an immune response in the same way it would following exposure to a disease but without the person getting the disease. If the person comes in contact with the disease in the future, the body is able to make an immune response fast enough to prevent the person developing the disease or developing a severe case of the disease. Knowing which vaccines you need is an important step toward protecting your health and that of your family and friends. Getting vaccines on time helps prevent illness before you’re exposed.

If you are sick, you may still be able to receive a vaccine, depending on which vaccine you need and the type and severity of your illness. Talk with your health care provider about the vaccines that might be recommended for your age, health status, and lifestyle.

Vaccine schedules are designed with you in mind. They are constructed to be as safe and as convenient as possible, without requiring unnecessary visits to your doctor or health care provider.

Find out which vaccines you may need at different times of life by reading about your age or health condition below.

The terms ‘vaccination’ and ‘immunization’ don’t mean quite the same thing. Vaccination is the term used for getting a vaccine — that is, actually getting the injection or taking an oral vaccine dose. Immunization refers to the process of both getting the vaccine and becoming immune to the disease following vaccination.

What are the types of vaccines?

There are several types of vaccines:

Live-attenuated vaccines use a weakened form of the germ
Inactivated vaccines use a killed version of the germ
Subunit, recombinant, polysaccharide, and conjugate vaccines use only specific pieces of the germ, such as its protein, sugar, or casing
Toxoid vaccines that use a toxin (harmful product) made by the germ
mRNA vaccines use messenger RNA, which gives your cells instructions for how to make a protein (or piece of a protein) of the germ
Viral vector vaccines use genetic material, which gives your cells instructions for making a protein of the germ. These vaccines also contain a different, harmless virus that helps get the genetic material into your cells.

Vaccines work in different ways, but they all spark an immune response. The immune response is the way your body defends itself against substances it sees as foreign or harmful. These substances include germs that can cause disease.

Are vaccines safe?

Vaccines are safe. They must go through extensive safety testing and evaluation before they are approved in the United States. Every authorized or approved vaccine goes through safety testing. Before a vaccine is ever recommended for use, it’s tested in labs. This process can take several years. The Food and Drug Administration (FDA) uses the information from these tests to decide whether to test the vaccine with people.

During a clinical trial, a vaccine is tested on people who volunteer to get vaccinated. Clinical trials usually start with 20 to 100 volunteers, but eventually include thousands of volunteers. These tests can take several years and answer important questions like:

Is the vaccine safe?
What dose (amount) works best?
How does the immune system react to it?

Throughout the process, FDA works closely with the company producing the vaccine to evaluate the vaccine’s safety and effectiveness. All safety concerns must be addressed before FDA licenses or authorizes a vaccine.

What ingredients are in my vaccine?

Today’s vaccines use only the ingredients they need to be safe and effective. Each ingredient in a vaccine serves a specific purpose. For example, vaccine ingredients may:

Help provide immunity (protection) against a specific disease
Help keep the vaccine safe and long lasting
Be used during the production of the vaccine

Ingredients provide immunity

Vaccines include ingredients to help your immune system respond and build immunity to a specific disease. For example:
- Antigens are very small amounts of weak or dead germs that can cause diseases. They help your immune system learn how to fight off infections faster and more effectively. The flu virus is an example of an antigen.
- Adjuvants, which are in some vaccines, are substances that help your immune system respond more strongly to a vaccine. This increases your immunity against the disease. Aluminum is an example of an adjuvant.

Ingredients keep vaccines safe and long lasting

Some ingredients help make sure a vaccine continues to work like it’s supposed to and that it stays free of outside germs and bacteria. For example:
- Preservatives, like thimerosal, protect the vaccine from outside bacteria or fungus. Today, preservatives are usually only used in vials (containers) of vaccines that have more than 1 dose. That’s because every time an individual dose is taken from the vial, it’s possible for harmful germs to get inside. Most vaccines are also available in single-dose vials and do not have preservatives in them.
- Stabilizers, like sugar or gelatin, help the active ingredients in vaccines continue to work while the vaccine is made, stored, and moved. Stabilizers keep the active ingredients in vaccines from changing because of something like a shift in temperature where the vaccine is being stored.

Ingredients are used during the production of vaccines

Some ingredients that are needed to produce the vaccine are no longer needed for the vaccine to work in a person. These ingredients are taken out after production so only tiny amounts are left in the final product. The very small amounts of these ingredients that remain in the final product aren’t harmful. Examples of ingredients used in some vaccines include:
- Cell culture (growth) material, like eggs, to help grow the vaccine antigens.
- Inactivating (germ-killing) ingredients, like formaldehyde, to weaken or kill viruses, bacteria, or toxins in the vaccine.
- Antibiotics, like neomycin, to help keep outside germs and bacteria from growing in the vaccine.

What are preservatives and why are they added to vaccines?

Preservatives are compounds that kill or prevent the growth of microorganisms, such as bacteria or fungi. Preservatives are used in vaccines to prevent bacterial or fungal growth in the event that the vaccine is accidentally contaminated, as might occur with repeated puncture of multi-dose vials. Vaccines, both in the United States and throughout other parts of the world, are commonly packaged in multi-dose vials. In some cases, preservatives are added during manufacture to prevent microbial growth; with changes in manufacturing technology, however, the need to add preservatives during the manufacturing process has decreased markedly.

Preservatives have been used in vaccines for over 70 years. The requirement for a preservative in multi-dose, multi-entry vials was placed into the Code of Federal Regulations (21 CFR 610.15) in January 1968 ¹. There are exceptions to this requirement for preservative, primarily involving the live-attenuated viral vaccines.

The general need for preservatives in multi-dose vials has been underscored by cases in which multi-dose vials that did not contain preservatives become contaminated during use and caused fatal infections in vaccine recipients.

Can people who are allergic to antibiotics get vaccinated?

Yes. However, if you have an allergy to antibiotics, it’s a good idea to talk with your doctor about getting vaccinated. But in general, antibiotics that people are most likely to be allergic to — like penicillin — aren’t used in vaccines.

Can people with egg allergies get vaccinated?

Yes. People with egg allergies can get any licensed, recommended flu vaccine that’s appropriate for their age. They no longer have to be watched for 30 minutes after getting the vaccine. People who have severe egg allergies should be vaccinated in a medical setting and be supervised by a health care professional who can recognize and manage severe allergic conditions.

Is the formaldehyde used in some vaccines dangerous?

No. If formaldehyde is used to help produce a vaccine, only very small amounts are left in the final product. This amount is so small that it’s not dangerous — in fact, there’s actually more formaldehyde found naturally in our bodies than there is in vaccines made with formaldehyde.

Is the aluminum used in some vaccines dangerous?

No. Vaccines made with aluminum have only a very small amount of aluminum in them. For decades, vaccines that include aluminum have been tested for safety — these studies have shown that using aluminum in vaccines is safe.

What is thimerosal (thiomersal)?

Thimerosal or thiomersal is a mercury-containing organic compound (ethylmercury). Thimerosal (thiomersal), which is approximately 50% mercury by weight, has been one of the most widely used preservatives in vaccines. Since the 1930s, it has been widely used as a preservative in a number of biological and drug products, including many vaccines, to help prevent potentially life threatening contamination with harmful microbes ². Thimerosal (thiomersal) has a different form of mercury (ethylmercury) than the kind that causes mercury poisoning (methylmercury). It’s safe to use ethylmercury in vaccines because it’s less likely to build up in the body — and because it’s used in very, very small amounts. Vaccines with trace amounts of thimerosal contain 1 microgram or less of mercury per dose. Ethylmercury is broken down by the body quickly and does not accumulate. Even so, most vaccines do not have any thimerosal (thiomersal) in them. If you’re concerned about thimerosal (thiomersal) or mercury in vaccines, talk with your doctor.

There is a robust body of peer-reviewed, scientific studies conducted in the United States and countries around the world that support the safety of thimerosal-containing vaccines ². The scientific evidence collected over the past 15 years does not show any evidence of harm, including serious neurodevelopmental disorders, from use of thimerosal in vaccines. Specifically, the Institute of Medicine (now known as the National Academy of Medicine), and others have concluded that the evidence favors rejection of a link between thimerosal and autism. ³ Scientific studies of the risk of other serious neurodevelopmental disorders have failed to support a causal link with thimerosal (thiomersal) ⁴, ⁵, ³, ⁶, ⁷, ⁸, ⁹, ¹⁰.

Current status of thimerosal in vaccines

The use of thimerosal as a preservative in U.S. FDA-licensed vaccines has significantly declined due to reformulation and development of new vaccines presented in single-dose containers.

All vaccines routinely recommended for children 6 years of age and younger in the U.S. are available in formulations that do not contain thimerosal.

As with pediatric vaccines, vaccines for adolescents and adults are available in formulations that do not contain thimerosal. (Note- one vaccine, Tetanus and Diphtheria Toxoids Adsorbed, single-dose presentation, manufactured by Mass Biologics utilizes thimerosal as part of its manufacturing process, not as a preservative, and a trace remains in the final presentation).

FDA-approved seasonal influenza vaccines are available in single-dose presentations that do not contain thimerosal as a preservative for use in infants, children, adults, the elderly and pregnant women. (Note- one vaccine, Fluvirin’s single-dose presentation utilizes thimerosal as part of its manufacturing process, not as a preservative, and a trace remains in the final presentation).

What happens in an immune response?

There are different steps in the immune response:

When a germ invades, your body sees it as foreign
Your immune system helps your body fight off the germ
Your immune system also remembers the germ. It will attack the germ if it ever invades again. This “memory” protects you against the disease that the germ causes. This type of protection is called immunity.

What is community immunity?

Community immunity, or herd immunity, is the idea that vaccines can help keep communities healthy.

Normally, germs can travel quickly through a community and make a lot of people sick. If enough people get sick, it can lead to an outbreak. But when enough people are vaccinated against a certain disease, it’s harder for that disease to spread to others. This type of protection means that the entire community is less likely to get the disease.

Community immunity is especially important for people who can’t get certain vaccines. For example, they may not be able to get a vaccine because they have weakened immune systems. Others may be allergic to certain vaccine ingredients. And newborn babies are too young to get some vaccines. Community immunity can help to protect them all.

Why are vaccines important?

Vaccines are important because they protect you against many diseases. These diseases can be very serious. So getting immunity from a vaccine is safer than getting immunity by being sick with the disease. And for a few vaccines, getting vaccinated can actually give you a better immune response than getting the disease would.

But vaccines don’t just protect you. They also protect the people around you through community immunity.

What is a vaccine schedule?

A vaccine, or immunization, schedule lists which vaccines are recommended for different groups of people. It includes who should get the vaccines, how many doses they need, and when they should get them. In the United States, the Centers for Disease Control and Prevention (CDC) publishes the vaccine schedule.

It’s important for both children and adults to get their vaccines according to the schedule. Following the schedule allows them to get protection from the diseases at exactly the right time.

How long do vaccinations take to work?

A child who has been given only 1 or 2 doses of the diphtheria, tetanus, and acellular pertussis vaccine (also known as DTaP) vaccine is only partially protected against diphtheria, tetanus and pertussis (whooping cough) and may become sick if exposed to these diseases until they have all the doses they need. However, some of the new vaccines, such as the meningococcal ACWY vaccine, provide long-lasting immunity after only one dose.

How long do vaccinations last?

The protective effect of immunizations is not always lifelong. Some, like tetanus vaccine, can last up to 10 years depending on your age, after which time a booster dose may be given. Some immunizations, such as whooping cough vaccine, give protection for about 5 years after a full course. Influenza immunization is needed every year due to frequent changes to the type of flu virus in the community.

Is everyone protected from disease by vaccination?

Even when all the doses of a vaccine have been given, not everyone is protected against the disease. Measles, mumps, rubella, tetanus, polio, hepatitis B and haemophilus influenzae type b (Hib) vaccines protect more than 95% of children who have completed the course. One dose of meningococcal ACWY vaccine at 12 months protects over 90% of children.

Three doses of whooping cough vaccine protect about 85% of children who have been immunized, and will reduce the severity of the disease in the other 15% if they do catch whooping cough. Booster doses are needed because immunity decreases over time.

Infants, Children, & Teens (birth to age 18)

Vaccinating your child is one of the most important steps you can take to protect their health and future. The childhood vaccine schedule designed to be as safe and as convenient as possible, and to protect children when they are at highest risk of complications from disease. Help protect your child’s health by learning about the vaccines they need and being sure to get the pre-teen and teenage vaccines on time. If your child did not get these vaccines at age 11 or 12, schedule an appointment to get them now. Vaccines are an important part of preventive care throughout life.

BCG vaccine

What is Tuberculosis

Tuberculosis is caused by a bacterium called Mycobacterium tuberculosis. The bacteria usually attack the lungs, but tuberculosis bacteria can attack any part of the body such as the kidney, spine, and brain. Not everyone infected with tuberculosis bacteria becomes sick. As a result, two tuberculosis-related conditions exist: latent tuberculosis infection and tuberculosis disease. If not treated properly, tuberculosis disease can be fatal.

BCG Vaccine

Bacille Calmette-Guérin (BCG) is a vaccine for tuberculosis disease. Many foreign-born persons have been BCG-vaccinated. BCG is used in many countries with a high prevalence of tuberculosis to prevent childhood tuberculous meningitis and miliary disease. However, BCG is not generally recommended for use in the United States because of the low risk of infection with Mycobacterium tuberculosis, the variable effectiveness of the vaccine against adult pulmonary tuberculosis, and the vaccine’s potential interference with tuberculin skin test reactivity. If you were vaccinated with BCG, you may have a positive reaction to a tuberculosis skin test. This reaction may be due to the BCG vaccine itself or due to infection with the tuberculosis bacteria. Your positive reaction is more likely to mean you have been infected with tuberculosis bacteria.

The BCG vaccine should be considered only for very select persons who meet specific criteria and in consultation with a tuberculosis expert.

BCG Vaccine Recommendations

In the United States, BCG should be considered for only very select people who meet specific criteria and in consultation with a tuberculosis expert. Health care providers who are considering BCG vaccination for their patients are encouraged to discuss this intervention with the tuberculosis control program in their area.

Children

BCG vaccination should only be considered for children who have a negative tuberculosis test and who are continually exposed, and cannot be separated from adults who:

Are untreated or ineffectively treated for tuberculosis disease, and the child cannot be given long-term primary preventive treatment for tuberculosis infection; or
Have tuberculosis disease caused by strains resistant to isoniazid and rifampin.

Health Care Workers

BCG vaccination of health care workers should be considered on an individual basis in settings in which:

A high percentage of tuberculosis patients are infected with tuberculosis strains resistant to both isoniazid and rifampin;
There is ongoing transmission of drug-resistant tuberculosis strains to health care workers and subsequent infection is likely; or
Comprehensive tuberculosis infection-control precautions have been implemented, but have not been successful.

Health care workers considered for BCG vaccination should be counseled regarding the risks and benefits associated with both BCG vaccination and treatment of latent tuberculosis infection.

BCG Vaccine Contraindications

Immunosuppression. BCG vaccination should not be given to persons who are immunosuppressed (e.g., persons who are HIV infected) or who are likely to become immunocompromised (e.g., persons who are candidates for organ transplant).

Pregnancy. BCG vaccination should not be given during pregnancy. Even though no harmful effects of BCG vaccination on the fetus have been observed, further studies are needed to prove its safety.

Testing for tuberculosis in BCG-Vaccinated People

Many people born outside of the United States have been BCG-vaccinated.

People who were previously vaccinated with BCG may receive a tuberculosis skin test to test for tuberculosis infection. Vaccination with BCG may cause a positive reaction to a tuberculosis skin test. A positive reaction to a tuberculosis skin test may be due to the BCG vaccine itself or due to infection with tuberculosis bacteria.

Tuberculosis blood tests (IGRAs), unlike the tuberculosis skin test, are not affected by prior BCG vaccination and are not expected to give a false-positive result in people who have received BCG.

For children under the age of five, the tuberculosis skin test is preferred over tuberculosis blood tests.

A positive tuberculosis skin test or tuberculosis blood test only tells that a person has been infected with tuberculosis bacteria. It does not tell whether the person has latent tuberculosis infection or has progressed to tuberculosis disease. Other tests, such as a chest x-ray and a sample of sputum, are needed to see whether the person has tuberculosis disease.

Chicken pox vaccine

What is Chickenpox

Chickenpox is a very contagious disease caused by the varicella-zoster virus (VZV). It causes a blister-like rash, itching, tiredness, and fever ¹¹. Chickenpox used to be very common in the United States.

The Centers for Disease Control and Prevention (CDC) recommends two doses of chickenpox vaccine for children, adolescents, and adults. Children should receive two doses of the chicken pox vaccine—the first dose at 12 through 15 months old and a second dose at 4 through 6 years old.

Chicken pox vaccine

Chickenpox vaccine is very effective. Two doses of the vaccine are about 98% effective at preventing chickenpox. Some people who are vaccinated against chickenpox may still get the disease. However, it is usually milder with fewer skin blisters and little or no fever.

Getting chickenpox vaccine is much safer than getting chickenpox disease. Most people who get chickenpox vaccine do not have any problems with it.

Types of Chickenpox Vaccine

There are two chickenpox vaccines that are licensed in the United States—Varivax^® and ProQuad^®.

Varivax^®

Contains only chickenpox vaccine
Licensed for use in children 12 months and older, adolescents, and adults
Can be given to children for their routine two doses of chickenpox vaccine at 12 through 15 months old and 4 through 6 years old

ProQuad^®

Contains a combination of measles, mumps, rubella, and varicella (chickenpox) vaccines, which is also called MMRV
Only licensed for use in children 12 months through 12 years old
Can be given to children for their routine two doses of chickenpox vaccine at 12 through 15 months old and 4 through 6 years old
Children who get the first dose of this vaccine at 12 to 23 months old may have a higher chance of a seizure caused by fever. This is in comparison to children who get the measles, mumps, and rubella vaccine and the chickenpox vaccine separately during a doctor visit. But, these seizures are not common. They may be scary for parents, but they are not harmful to children. Talk with a doctor if you have questions.

Chickenpox vaccine Schedule

For Infants, Children, and Adults

Children under 13 years old should get two doses of the chickenpox vaccine at these ages:

1st dose: 12 through 15 months
2nd dose: 4 through 6 years (may be given earlier, if at least three months after the 1st dose)

The second dose may be given at an earlier age if it is given at least three months after the first dose.

People 13 years or older (who have never had chickenpox and never received chickenpox vaccine) should get two doses at least 28 days apart.

ProQuad® (MMRV) is licensed for use in children 12 months to 12 years old. Your child’s doctor can help you decide which vaccine to use.

However, pregnant women should wait to get the chickenpox vaccine until after they have given birth. Women should not get pregnant for 1 month after getting the chickenpox vaccine.

Who Needs Chicken pox Vaccine

Children under age 13 years should get two doses:

First dose at age 12 through 15 months
Second dose at age 4 through 6 years.

The second dose may be given at an earlier age if it is given at least 3 months after the first dose.

People 13 years of age and older who have never had chickenpox or received chickenpox vaccine should get two doses, at least 28 days apart.

Chickenpox vaccination is especially important for—

Healthcare professionals
People who care for or are around others with weakened immune systems
Teachers
Child care workers
Residents and staff in nursing homes and residential settings
College students
Inmates and staff of correctional institutions
Military personnel
Non-pregnant women of child-bearing age
Adolescents and adults living with children
International travelers.

Some people with weakened immune systems who do not have immunity against chickenpox may be considered for vaccination after talking with their doctor, including people—

with HIV-infection
with cancer, but whose disease is in remission
on low or high-dose steroids.

Who Should Not Get Chickenpox Vaccine

You do not need to get the chickenpox vaccine if you have evidence of immunity against the disease.

Some people should not get chickenpox vaccine or they should wait.

People should not get chickenpox vaccine if they have ever had a life-threatening allergic reaction to a previous dose of chickenpox vaccine or any component of the vaccine, including gelatin or the antibiotic neomycin.
People who are moderately or severely ill at the time the shot is scheduled should usually wait until they recover before getting chickenpox vaccine.
Pregnant women should not get chickenpox vaccine. They should wait to get chickenpox vaccine until after they have given birth. Women should not get pregnant for 1 month after getting chickenpox vaccine.
People with the following conditions should check with their doctor about whether they should get chickenpox vaccine, including anyone who:
- Has HIV/AIDS or another disease that affects the immune system
- Is being treated with drugs that affect the immune system, such as steroids, for 2 weeks or longer
- Has any kind of cancer
- Is getting cancer treatment with radiation or drugs
People who recently had a transfusion or were given other blood products should ask their doctor when they may get chickenpox vaccine.

Getting Vaccinated After You Are Exposed to Chickenpox

If you do not have immunity against chickenpox and are exposed to someone with this disease or shingles, talk with your doctor about getting chickenpox vaccine.

You should get chickenpox vaccine within 3 to 5 days of being exposed.

You need two doses of vaccine at two different times. For more information, see Who Needs Chickenpox Vaccine.

If you previously got one dose of chickenpox vaccine, you should get a second dose.

Getting vaccinated after you are exposed to someone with chickenpox can—

prevent the disease or make it less serious
protect you from chickenpox if you are exposed again in the future

A doctor can prescribe a medicine to make chickenpox less severe. This is especially important for people who are exposed to chickenpox and do not have immunity against the disease and are not eligible for vaccination.

Assessing Immunity to Chicken pox Varicella virus infection

Evidence of immunity to Chickenpox (varicella virus) includes any of the following:

Documentation of age-appropriate varicella vaccination;
Preschool-age children (i.e., age 12 months through 3 years): 1 dose
School-age children, adolescents, adults: 2 doses
Laboratory evidence of immunity or laboratory confirmation of disease
Birth in the United States before 1980 (Should not be considered evidence of immunity for health care personnel, pregnant women, and immunocompromised persons)
Diagnosis or verification of a history of varicella or herpes zoster by a health care provider

To verify a history of varicella, your health care providers should inquire about:

an epidemiologic link to another typical varicella case or to a laboratory confirmed case, or
evidence of laboratory confirmation, if testing was performed at the time of acute disease

Persons who have neither an epidemiologic link nor laboratory confirmation of varicella should not be considered as having a valid history of disease. For these persons, a second dose of vaccine is recommended if they previously received only one dose. If a health care provider verifies the diagnosis based on the above criteria, then vaccination is not needed.

Chickenpox vaccine side effects

Varivax^®

Frequently reported (≥10%) adverse reactions in children ages 1 to 12 years include ¹²:

fever ≥102.0°F (38.9°C): 14.7%
injection-site complaints: 19.3%.

Frequently reported (≥10%) adverse reactions in adolescents and adults ages 13 years and older include ¹²:

fever ≥100.0°F (37.8°C): 10.2%
injection-site complaints: 24.4%

Other reported adverse reactions in all age groups include:

varicella-like rash (injection site)
varicella-like rash (generalized).

ProQuad^®

The most frequent vaccine-related adverse events reported in ≥5% of subjects vaccinated with ProQuad were ¹³:

injection-site reactions (pain/tenderness/soreness, erythema, and swelling)
fever
irritability.

Systemic vaccine-related adverse events that were reported at a significantly greater rate in recipients of ProQuad than in recipients of the component vaccines administered concomitantly were:

fever
measles-like rash.

DTaP Vaccine

Diphtheria, tetanus, and pertussis (DTaP) are serious diseases caused by bacteria. Diphtheria and pertussis are spread from person to person. Tetanus enters the body through cuts or wounds.

DIPHTHERIA causes a thick covering in the back of the throat.

It can lead to breathing problems, paralysis, heart failure, and even death.

TETANUS (Lockjaw) causes painful tightening of the muscles, usually all over the body.

It can lead to “locking” of the jaw so the victim cannot open his mouth or swallow. Tetanus leads to death in up to 2 out of 10 cases.

PERTUSSIS (Whooping Cough) causes coughing spells so bad that it is hard for infants to eat, drink, or breathe. These spells can last for weeks.

It can lead to pneumonia, seizures (jerking and staring spells), brain damage, and death.

Diphtheria, tetanus, and pertussis vaccine (DTaP) can help prevent these diseases. Most children who are vaccinated with DTaP will be protected throughout childhood. Many more children would get these diseases if we stopped vaccinating.

DTaP is a safer version of an older vaccine called DTP. DTP is no longer used in the United States.

DTaP Vaccine

Who should get DTaP vaccine and when ?

Children should get 5 doses of DTaP vaccine, one dose at each of the following ages:

2 months
4 months
6 months
15-18 months
4-6 years

DTaP may be given at the same time as other vaccines.

Some children should not get DTaP vaccine or should wait

Children with minor illnesses, such as a cold, may be vaccinated. But children who are moderately or severely ill should usually wait until they recover before getting DTaP vaccine.
Any child who had a life-threatening allergic reaction after a dose of DTaP should not get another dose.
Any child who suffered a brain or nervous system disease within 7 days after a dose of DTaP should not get another dose.
Talk with your doctor if your child:
- had a seizure or collapsed after a dose of DTaP,
- cried non-stop for 3 hours or more after a dose of DTaP,
- had a fever over 105°F after a dose of DTaP.

Ask your doctor for more information. Some of these children should not get another dose of pertussis vaccine, but may get a vaccine without pertussis, called DT.

Older children and adults

DTaP is not licensed for adolescents, adults, or children 7 years of age and older.

But older people still need protection. A vaccine called Tdap is similar to DTaP. A single dose of Tdap is recommended for people 11 through 64 years of age. Another vaccine, called Td, protects against tetanus and diphtheria, but not pertussis. It is recommended every 10 years. There are separate Vaccine Information Statements for these vaccines.

DTaP vaccine side-effects

Getting diphtheria, tetanus, or pertussis disease is much riskier than getting DTaP vaccine.

However, a vaccine, like any medicine, is capable of causing serious problems, such as severe allergic reactions. The risk of DTaP vaccine causing serious harm, or death, is extremely small.

Mild Problems (Common)

Fever (up to about 1 child in 4)
Redness or swelling where the shot was given (up to about 1 child in 4)
Soreness or tenderness where the shot was given (up to about 1 child in 4)

These problems occur more often after the 4th and 5th doses of the DTaP series than after earlier doses. Sometimes the 4th or 5th dose of DTaP vaccine is followed by swelling of the entire arm or leg in which the shot was given, lasting 1-7 days (up to about 1 child in 30).

Other mild problems include:

Fussiness (up to about 1 child in 3)
Tiredness or poor appetite (up to about 1 child in 10)
Vomiting (up to about 1 child in 50)

These problems generally occur 1-3 days after the shot.

Moderate Problems (Uncommon)

Seizure (jerking or staring) (about 1 child out of 14,000)
Non-stop crying, for 3 hours or more (up to about 1 child out of 1,000)
High fever, over 105°F (about 1 child out of 16,000)

Severe Problems (Very Rare)

Serious allergic reaction (less than 1 out of a million doses)
Several other severe problems have been reported after DTaP vaccine. These include:
Long-term seizures, coma, or lowered consciousness
Permanent brain damage.

These are so rare it is hard to tell if they are caused by the vaccine.

Controlling fever is especially important for children who have had seizures, for any reason. It is also important if another family member has had seizures. You can reduce fever and pain by giving your child an aspirin-free pain reliever when the shot is given, and for the next 24 hours, following the package instructions.

Flu vaccine

What is Influenza (flu)

Influenza (flu) is a contagious respiratory illness caused by influenza viruses that infect the nose, throat, and lungs. It can cause mild to severe illness, and can lead to hospitalization and death. Every year in the United States, millions of people are sickened, hundreds of thousands are hospitalized and thousands or tens of thousands of people die from the flu.

Anyone can get the flu (even healthy people) and serious problems related to the flu can happen at any age, but some people are a higher risk of developing serious flu-related complications if they get sick. This includes people 65 years and older, people of any age with certain chronic medical conditions (such as diabetes, asthma, or heart disease), pregnant women, and young children.

The best way and most important step to prevent the flu is by getting a flu vaccine each year. The Centers for Disease Control and Prevention (CDC) recommends that everyone 6 months of age and older get a flu vaccine each year. Flu vaccination can reduce flu illnesses, doctors’ visits, and missed work and school due to flu, as well as prevent flu-related hospitalizations.

Influenza Symptoms

Influenza (also known as the flu) is a contagious respiratory illness caused by flu viruses. It can cause mild to severe illness, and at times can lead to death. The flu is different from a cold. The flu usually comes on suddenly. People who have the flu often feel some or all of these symptoms:

Fever* or feeling feverish/chills
Cough
Sore throat
Runny or stuffy nose
Muscle or body aches
Headaches
Fatigue (tiredness)
Some people may have vomiting and diarrhea, though this is more common in children than adults.

* It’s important to note that not everyone with flu will have a fever.

Flu Complications

Most people who get influenza will recover in several days to less than two weeks, but some people will develop complications as a result of the flu. A wide range of complications can be caused by influenza virus infection of the upper respiratory tract (nasal passages, throat) and lower respiratory tract (lungs). While anyone can get sick with flu and become severely ill, some people are more likely to experience severe flu illness. Young children, adults aged 65 years and older, pregnant women, and people with certain chronic medical conditions are among those groups of people who are at high risk of serious flu complications, possibly requiring hospitalization and sometimes resulting in death. For example, people with chronic lung disease are at higher risk of developing severe pneumonia.

Sinus and ear infections are examples of moderate complications from flu, while pneumonia is a serious flu complication that can result from either influenza virus infection alone or from co-infection of flu virus and bacteria. Other possible serious complications triggered by flu can include inflammation of the heart (myocarditis), brain (encephalitis) or muscle (myositis, rhabdomyolysis) tissues, and multi-organ failure (for example, respiratory and kidney failure). Flu virus infection of the respiratory tract can trigger an extreme inflammatory response in the body and can lead to sepsis, the body’s life-threatening response to infection. Flu also can make chronic medical problems worse. For example, people with asthma may experience asthma attacks while they have the flu, and people with chronic heart disease may experience a worsening of this condition triggered by flu.

Flu Vaccine

Everyone 6 months and older is recommended for annual flu vaccination with rare exception. For the 2016-2017 season, the Centers for Disease Control and Prevention (CDC) recommends use of injectable flu vaccines–inactivated influenza vaccine (or IIV) or the recombinant influenza vaccine (RIV). The nasal spray flu vaccine (live attenuated influenza vaccine or LAIV) should not be used during 2016-2017. You should take precautions or talk to your doctor or other health care professional before vaccination. Talk to your doctor or nurse if you have any questions regarding which flu vaccine is best for you and your family.
All persons aged 6 months and older are recommended for annual vaccination, with rare exception.

Vaccination is particularly important for people who are at high risk for serious flu complications from influenza.

Flu Vaccine Effectiveness

Influenza vaccine effectiveness can vary from year to year and among different age and risk groups.

The Centers for Disease Control and Prevention (CDC) conducts studies each year to determine how well the influenza (flu) vaccine protects against flu illness. While vaccine effectiveness can vary, recent studies show that flu vaccination reduces the risk of flu illness by between 40% and 60% among the overall population during seasons when most circulating flu viruses are well-matched to the flu vaccine. In general, current flu vaccines tend to work better against influenza B and influenza A(H1N1) viruses and offer lower protection against influenza A(H3N2) viruses.

What are factors that influence how well the vaccine works ?

How well the flu vaccine works (or its ability to prevent flu illness) can range widely from season to season. The vaccine’s effectiveness also can vary depending on who is being vaccinated. At least two factors play an important role in determining the likelihood that flu vaccine will protect a person from flu illness:

characteristics of the person being vaccinated (such as their age and health), and
the similarity or “match” between the flu viruses the flu vaccine is designed to protect against and the flu viruses spreading in the community.

During years when the flu vaccine is not well matched to circulating influenza viruses, it is possible that no benefit from flu vaccination may be observed. During years when there is a good match between the flu vaccine and circulating viruses, it is possible to measure substantial benefits from flu vaccination in terms of preventing flu illness. However, even during years when the flu vaccine match is good, the benefits of flu vaccination will vary, depending on various factors like the characteristics of the person being vaccinated, what influenza viruses are circulating that season and even, potentially, which flu vaccine was used.

Each flu season researchers try to determine how well flu vaccines work as a public health intervention. Estimates of how well a flu vaccine works can vary based on study design, outcome(s) measured, population studied and the season in which the flu vaccine was studied. These differences can make it difficult to compare one study’s results with another’s.

While determining how well a flu vaccine works is challenging, in general, recent studies have supported the conclusion that flu vaccination benefits public health, especially when the flu vaccine is well matched to circulating flu viruses.

What are the benefits of flu vaccination ?

While how well the flu vaccine works can vary, there are many reasons to get a flu vaccine each year.

Flu vaccination can keep you from getting sick with flu.
Flu vaccination can reduce the risk of flu-associated hospitalization, including among children and older adults.
Vaccine effectiveness for the prevention of flu-associated hospitalizations was similar to vaccine effectiveness against flu illness resulting in doctor’s visits in a comparative study published in 2016.
Flu vaccination is an important preventive tool for people with chronic health conditions.
Flu vaccination has been associated with lower rates of some cardiac (heart) events among people with heart disease, especially among those who experienced a cardiac event in the past year.
Flu vaccination also has been associated with reduced hospitalizations among people with diabetes (79%) and chronic lung disease (52%).
Vaccination helps protect women during and after pregnancy. Getting vaccinated can also protect a baby after birth from flu. (Mom passes antibodies onto the developing baby during her pregnancy.)
A study that looked at flu vaccine effectiveness in pregnant women found that vaccination reduced the risk of flu-associated acute respiratory infection by about one half.
There are studies that show that flu vaccine in a pregnant woman can reduce the risk of flu illness in her baby by up to half. This protective benefit was observed for several months after birth.
And a 2017 study was the first of its kind to show that flu vaccination can significantly reduce a child’s risk of dying from influenza.
Flu vaccination also may make your illness milder if you do get sick. (For example a 2017 study showed that flu vaccination reduced deaths, intensive care unit (ICU) admissions, ICU length of stay, and overall duration of hospitalization among hospitalized flu patients.)
Getting vaccinated yourself also protects people around you, including those who are more vulnerable to serious flu illness, like babies and young children, older people, and people with certain chronic health conditions.

Is the flu vaccine effective against all types of flu and cold viruses ?

Seasonal flu vaccines are designed to protect against infection and illness caused by the three or four influenza viruses (depending on vaccine) that research indicates will be most common during the flu season. “Trivalent” flu vaccines are formulated to protect against three flu viruses, and “quadrivalent” flu vaccines protect against four flu viruses. Flu vaccines do NOT protect against infection and illness caused by other viruses that can also cause flu-like symptoms. There are many other viruses besides flu viruses that can result in flu-like illness* (also known as influenza-like illness or “ILI”) that spread during the flu season. These non-flu viruses include rhinovirus (one cause of the “common cold”) and respiratory syncytial virus (RSV), which is the most common cause of severe respiratory illness in young children, as well as a leading cause of death from respiratory illness in those aged 65 years and older.

How effective is the flu vaccine in the elderly ?

Older people with weaker immune systems often have a lower protective immune response after flu vaccination compared to younger, healthier people. This can make them more susceptible to the flu. Although immune responses may be lower in the elderly, vaccine effectiveness has been similar in most flu seasons among older adults and those with chronic health conditions compared to younger, healthy adults.

If older people have weaker immune responses to flu vaccination, should they still get vaccinated ?

Despite the fact that older adults (65 years of age and older) have weaker immune responses to vaccine flu vaccines, there are many reasons why people in that age group should be vaccinated each year.

First, people aged 65 and older are at increased risk of serious illness, hospitalization and death from the flu.
Second, while the effectiveness of the flu vaccine can be low among older people, there are seasons when significant benefit can be observed. Even if the vaccine provides less protection in older adults than it might in younger people, some protection is better than no protection at all, especially in this high risk group.
Third, flu vaccine may protect against more serious outcomes like hospitalization and death. For example, one study concluded that one death was prevented for every 4,000 people vaccinated against the flu.
In frail elderly adults, hospitalizations can mark the beginning of a significant decline in overall health and mobility, potentially resulting in loss of the ability to live independently or to complete basic activities of daily living. While the protection elderly adults obtain from flu vaccination can vary significantly, a yearly flu vaccination is still the best protection currently available against the flu.
There is some data to suggest that flu vaccination may reduce flu illness severity; so while someone who is vaccinated may still get infected, their illness may be milder.
Fourth, it’s important to remember that people who are 65 and older are a diverse group and often are different from one another in terms of their overall health, level of activity and mobility, and behavior when it comes to seeking medical care. This group includes people who are healthy and active and have responsive immune systems, as well as those who have underlying medical conditions that may weaken their immune system and their bodies’ ability to respond to vaccination. Therefore, when evaluating the benefits of flu vaccination, it is important to look at a broader picture than what one study’s findings can present.

How effective is the flu vaccine in children ?

Vaccination has consistently been found to provide a similar level of protection against flu illness in children to that seen among healthy adults.

In one study, flu vaccine effectiveness was higher among children who received two doses of flu vaccine the first season that they were vaccinated (as recommended) compared to “partially vaccinated” children who only received a single dose of flu vaccine. However, the partially vaccinated children still received some protection.

Flu vaccine can prevent severe, life-threatening illness in children, for example:

A 2014 study showed that flu vaccine reduced children’s risk of flu-related pediatric intensive care unit (PICU) admission by 74% during flu seasons from 2010-2012.
In 2017, a study in the journal Pediatrics was the first of its kind to show that flu vaccination also significantly reduced a child’s risk of dying from the flu.
The study, which looked at data from four flu seasons between 2010 and 2014, found that flu vaccination reduced the risk of flu-associated death by half (51 percent) among children with underlying high-risk medical conditions and by nearly two-thirds (65 percent) among healthy children.

What kinds of flu vaccines are available ?

The Centers for Disease Control and Prevention (CDC) recommends use of injectable influenza vaccines (including inactivated influenza vaccines and recombinant influenza vaccines) during 2017-2018. The nasal spray flu vaccine (live attenuated influenza vaccine or LAIV) should not be used during 2017-2018 ¹⁴.

Both trivalent (three-component) and quadrivalent (four-component) flu vaccines will be available.

Trivalent flu vaccines include:

Standard-dose trivalent shots (IIV3) that are manufactured using virus grown in eggs. Different flu shots are approved for different age groups. Most flu shots are given in the arm (muscle) with a needle. One trivalent vaccine formulation can be given with a jet injector, for persons aged 18 through 64 years.
A high-dose trivalent shot, approved for people 65 and older.
A recombinant trivalent shot that is egg-free, approved for people 18 years and older, including pregnant women.
A trivalent flu shot made with adjuvant (an ingredient of a vaccine that helps create a stronger immune response in the patient’s body), approved for people 65 years of age and older (new this season).

Quadrivalent flu vaccines include:

Quadrivalent flu shots approved for use in different age groups, including children as young as 6 months.
An intradermal quadrivalent flu shot, which is injected into the skin instead of the muscle and uses a much smaller needle than the regular flu shot. It is approved for people 18 through 64 years of age.
A quadrivalent flu shot containing virus grown in cell culture, which is approved for people 4 years of age and older.
A recombinant quadrivalent flu shot approved for people 18 years of age and older, including pregnant women (new this season).

Who should get vaccinated this season ?

Everyone 6 months of age and older should get a flu vaccine every season. This recommendation has been in place since February 24, 2010 when CDC’s Advisory Committee on Immunization Practices (ACIP) voted for “universal” flu vaccination in the United States to expand protection against the flu to more people.

Vaccination to prevent influenza is particularly important for people who are at high risk of serious complications from influenza. See People at High Risk of Developing Flu-Related Complications for a full list of age and health factors that confer increased risk.

Who Should Not Be Vaccinated ?

CDC recommends use of a flu shot; either an inactivated influenza vaccine or (IIV) or a recombinant influenza vaccine (RIV). The nasal spray flu vaccine (live attenuated influenza vaccine or LAIV) should not be used during 2017-2018. Different flu vaccines are approved for use in different groups of people. Factors that can determine a person’s suitability for vaccination, or vaccination with a particular vaccine, include a person’s age, health (current and past) and any allergies to flu vaccine or its components.

People who cannot get a flu shot.
People who should talk to their doctor before getting the flu shot.

When should I get vaccinated ?

You should get a flu vaccine now, if you haven’t gotten one already this season. It’s best to get vaccinated before flu begins spreading in your community. It takes about two weeks after vaccination for antibodies to develop in the body that protect against flu. CDC recommends that people get a flu vaccine by the end of October, if possible. Getting vaccinated later, however, can still be beneficial and vaccination should continue to be offered throughout the flu season, even into January or later.

Children who need two doses of vaccine to be protected should start the vaccination process sooner, because the two doses must be given at least four weeks apart.

Where can I get a flu vaccine ?

Flu vaccines are offered in many locations, including doctor’s offices, clinics, health departments, pharmacies and college health centers, as well as by many employers, and even in some schools.

Even if you don’t have a regular doctor or nurse, you can get a flu vaccine somewhere else, like a health department, pharmacy, urgent care clinic, and often your school, college health center, or workplace.

Why do I need a flu vaccine every year ?

A flu vaccine is needed every season for two reasons. First, the body’s immune response from vaccination declines over time, so an annual vaccine is needed for optimal protection. Second, because flu viruses are constantly changing, the formulation of the flu vaccine is reviewed each year and sometimes updated to keep up with changing flu viruses. For the best protection, everyone 6 months and older should get vaccinated annually.

Does flu vaccine work right away ?

No. It takes about two weeks after vaccination for antibodies to develop in the body and provide protection against influenza virus infection. That’s why it’s better to get vaccinated early in the fall, before the flu season really gets under way.

Can I get seasonal flu even though I got a flu vaccine this year ?

Yes. There is still a possibility you could get the flu even if you got vaccinated. The ability of flu vaccine to protect a person depends on various factors, including the age and health status of the person being vaccinated, and also the similarity or “match” between the viruses used to make the vaccine and those circulating in the community. If the viruses in the vaccine and the influenza viruses circulating in the community are closely matched, vaccine effectiveness is higher. If they are not closely matched, vaccine effectiveness can be reduced. However, it’s important to remember that even when the viruses are not closely matched, the vaccine can still protect many people and prevent flu-related complications. Such protection is possible because antibodies made in response to the vaccine can provide some protection (called cross-protection) against different but related influenza viruses.

Is it true that getting vaccinated repeatedly can reduce vaccine effectiveness ?

Some studies do suggest that flu vaccine effectiveness may be higher in people receiving flu vaccine for the first time compared to people who have been vaccinated more than once; other studies have found no evidence that repeat vaccination results in a person being less-protected against flu.

Immune responses to vaccination may be higher among people who were not vaccinated in a previous season, but repeatedly vaccinated people (i.e., people who receive the flu vaccine each year) may still have increased immune responses after vaccination.

Two reviews of multiple studies have found that for people vaccinated in the prior season, vaccination in the subsequent season provides additional protection against flu.

Information regarding flu vaccination history is particularly important to these types of evaluations, and can be difficult to confirm, as accurate vaccination records are not always readily available. People who choose to get vaccinated every year may have different characteristics and susceptibility to flu compared to those who do not seek vaccination every year. CDC thinks that these findings merit further investigation to understand the immune response to repeat vaccination. CDC supports continued efforts to monitor the effects of repeat vaccination each year. However, based on the substantial burden of flu in the United States, and on the fact that most studies point to vaccination benefits, CDC recommends that yearly flu vaccination remains the first and most important step in protecting against flu and its complications.

Hepatitis A vaccine

What is Hepatitis A

Hepatitis A is a serious liver disease caused by the hepatitis A virus (HAV). Hepatitis A can affect anyone. Hepatitis A virus is spread from person to person through contact with the feces (stool) of people who are infected, which can easily happen if someone does not wash his or her hands properly. You can also get hepatitis A from food, water, or objects contaminated with hepatitis A virus.

Symptoms of hepatitis A can include:

fever, fatigue, loss of appetite, nausea, vomiting, and/or joint pain
severe stomach pains and diarrhea (mainly in children), or
jaundice (yellow skin or eyes, dark urine, clay-colored bowel movements).

These symptoms usually appear 2 to 6 weeks after exposure and usually last less than 2 months, although some people can be ill for as long as 6 months. If you have hepatitis A you may be too ill to work.

Children often do not have symptoms, but most adults do. You can spread HAV without having symptoms.

Hepatitis A can cause liver failure and death, although this is rare and occurs more commonly in persons 50 years of age or older and persons with other liver diseases, such as hepatitis B or C.

Hepatitis A vaccines are available for long-term prevention of hepatitis A virus infection in persons 1 year of age and older. Good personal hygiene and proper sanitation can also help prevent the spread of hepatitis A.

Hepatitis A vaccines were recommended in the United States beginning in 1996. Since then, the number of cases reported each year in the U.S. has dropped from around 31,000 cases to fewer than 1,500 cases.

Hepatitis A vaccine

Hepatitis A vaccine is an inactivated (killed) vaccine. You will need 2 doses for long-lasting protection. These doses should be given at least 6 months apart.

Children are routinely vaccinated between their first and second birthdays (12 through 23 months of age). Older children and adolescents can get the vaccine after 23 months. Adults who have not been vaccinated previously and want to be protected against hepatitis A can also get the vaccine.

You should get hepatitis A vaccine if you:

are traveling to countries where hepatitis A is common,
you live in a community with a high rate of hepatitis A,
are a man who has sex with other men,
use illegal drugs,
have a chronic liver disease such as hepatitis B or hepatitis C,
are being treated with clotting-factor concentrates,
work with hepatitis A-infected animals or in a hepatitis A research laboratory, or
expect to have close personal contact with an international adoptee from a country where hepatitis A is common

Ask your healthcare provider if you want more information about any of these groups.

There are no known risks to getting hepatitis A vaccine at the same time as other vaccines.

Who should not get Hepatitis A vaccine

Tell the person who is giving you the vaccine:

If you have any severe, life-threatening allergies. Signs of a severe allergic reaction can include hives, swelling of the face and throat, difficulty breathing, a fast heartbeat, dizziness, and weakness. These would usually start a few minutes to a few hours after the vaccination. If you ever had a life-threatening allergic reaction after a dose of hepatitis A vaccine, or have a severe allergy to any part of this vaccine, you may be advised not to get vaccinated. Ask your health care provider if you want information about vaccine components.
If you think it is a severe allergic reaction or other emergency that can’t wait, call your local emergency number and get to the nearest hospital. Otherwise, call your clinic.
If you are not feeling well. If you have a mild illness, such as a cold, you can probably get the vaccine today. If you are moderately or severely ill, you should probably wait until you recover. Your doctor can advise you.

Risks of a Hepatitis A vaccine reaction

With any medicine, including vaccines, there is a chance of side effects. These are usually mild and go away on their own, but serious reactions are also possible.

Most people who get hepatitis A vaccine do not have any problems with it.

Minor problems following hepatitis A vaccine include:

soreness or redness where the shot was given
low-grade fever
headache
tiredness

If these problems occur, they usually begin soon after the shot and last 1 or 2 days.

Your doctor can tell you more about these reactions.

Other problems that could happen after Hepatitis A vaccination:

People sometimes faint after a medical procedure, including vaccination. Sitting or lying down for about 15 minutes can help prevent fainting, and injuries caused by a fall. Tell your provider if you feel dizzy, or have vision changes or ringing in the ears.
Some people get shoulder pain that can be more severe and longer lasting than the more routine soreness that can follow injections. This happens very rarely.
Any medication can cause a severe allergic reaction. Such reactions from a vaccine are very rare, estimated at about 1 in a million doses, and would happen within a few minutes to a few hours after the vaccination.

As with any medicine, there is a very remote chance of a vaccine causing a serious injury or death.

Hepatitis B vaccine

What is Hepatitis B

Hepatitis B is a serious disease caused by a virus that attacks the liver. The virus, which is called hepatitis B virus (HBV), can cause lifelong infection, cirrhosis (scarring) of the liver, liver cancer, liver failure, and death.

Hepatitis B vaccine is available for all age groups to prevent hepatitis B virus infection and its consequences, including liver cancer, liver failure and cirrhosis.

Hepatitis B virus infection can be either acute or chronic.

Acute hepatitis B virus infection is a short-term illness that occurs within the first 6 months after someone is exposed to the hepatitis B virus. This can lead to:

fever, fatigue, loss of appetite, nausea, and/or vomiting
jaundice (yellow skin or eyes, dark urine, clay-colored bowel movements)
pain in muscles, joints, and stomach

Chronic hepatitis B virus infection is a long-term illness that occurs when the hepatitis B virus remains in a person’s body. Most people who go on to develop chronic hepatitis B do not have symptoms, but it is still very serious and can lead to:

liver damage (cirrhosis)
liver cancer
death

Chronically-infected people can spread hepatitis B virus to others, even if they do not feel or look sick themselves. Up to 1.4 million people in the United States may have chronic hepatitis B infection. About 90% of infants who get hepatitis B become chronically infected and about 1 out of 4 of them dies.

Hepatitis B is spread when blood, semen, or other body fluid infected with the Hepatitis B virus enters the body of a person who is not infected. People can become infected with the virus through:

Birth (a baby whose mother is infected can be infected at or after birth)
Sharing items such as razors or toothbrushes with an infected person
Contact with the blood or open sores of an infected person
Sex with an infected partner
Sharing needles, syringes, or other drug-injection equipment
Exposure to blood from needlesticks or other sharp instruments

Each year about 2,000 people in the United States die from hepatitis B-related liver disease.

Hepatitis B Vaccine

Hepatitis B vaccine is made from parts of the hepatitis B virus. It cannot cause hepatitis B infection. The vaccine is usually given as 3 or 4 shots over a 6-month period.

Who Needs to be Vaccinated against Hepatitis B ?

Infants should get their first dose of hepatitis B vaccine at birth and will usually complete the series at 6 months of age.
All children and adolescents younger than 19 years of age should get their first dose of hepatitis B vaccine at birth and should have completed the vaccine series by 6 through 18 months of age.
Children and adolescents through 18 years of age who did not get the vaccine when they were younger should also be vaccinated.

As an adult, you should get the hepatitis B vaccine if:

You have sex with or live in the same house as a person with hepatitis B virus infection.
You have sex with more than one partner.
You seek care in a clinic for sexually transmitted diseases, HIV testing or treatment, or drug treatment.
You are a man who has sex with other men.
You inject drugs.
You have a job that involves contact with human blood*.
You are on the staff of, or a client in, an institution for the developmentally disabled*.
You are a hemodialysis patient or have end-stage renal disease.
You have HIV infection.
You are a dialysis patient.
You have chronic liver disease, kidney disease, HIV infection, or diabetes.
You have diabetes and are under age 60.
You live or travel for more than 6 months a year in countries where hepatitis B is common.
You seek care in a clinic for sexually transmitted diseases, HIV testing, or drug treatment.
You are a prisoner in a correctional facility.
You are a victim of sexual assault or abuse.
You want to be protected from hepatitis B virus infection.

Who should not get hepatitis B vaccine

Tell the person who is giving the vaccine:

If you have any severe, life-threatening allergies. Signs of a severe allergic reaction can include hives, swelling of the face and throat, difficulty breathing, a fast heartbeat, dizziness, and weakness. These would usually start a few minutes to a few hours after the vaccination. If you ever had a life-threatening allergic reaction after a dose of hepatitis A vaccine, or have a severe allergy to any part of this vaccine, you may be advised not to get vaccinated. Ask your health care provider if you want information about vaccine components.
If you think it is a severe allergic reaction or other emergency that can’t wait, call your local emergency number and get to the nearest hospital. Otherwise, call your clinic.
If you are not feeling well. If you have a mild illness, such as a cold, you can probably get the vaccine today. If you are moderately or severely ill, you should probably wait until you recover. Your doctor can advise you.

Hepatitis B vaccine side-effects

With any medicine, including vaccines, there is a chance of side effects. These are usually mild and go away on their own, but serious reactions are also possible.

Most people who get hepatitis B vaccine do not have any problems with it.

Minor problems following hepatitis B vaccine include:

soreness where the shot was given
temperature of 99.9°F or higher

If these problems occur, they usually begin soon after the shot and last 1 or 2 days.

Your doctor can tell you more about these reactions.

Other problems that could happen after this vaccine:

People sometimes faint after a medical procedure, including vaccination. Sitting or lying down for about 15 minutes can help prevent fainting and injuries caused by a fall. Tell your provider if you feel dizzy, or have vision changes or ringing in the ears.
Some people get shoulder pain that can be more severe and longer-lasting than the more routine soreness that can follow injections. This happens very rarely.
Any medication can cause a severe allergic reaction. Such reactions from a vaccine are very rare, estimated at about 1 in a million doses, and would happen within a few minutes to a few hours after the vaccination.

As with any medicine, there is a very remote chance of a vaccine causing a serious injury or death.

HIB vaccine

What is Hib (Haemophilus influenzae type b) disease ?

Haemophilus influenzae is a type of bacteria that mainly causes illness in babies and children younger than 5 years old ¹⁵. These bacteria can cause infections in people of all ages ranging from mild, such as an ear infection, to severe, such as a bloodstream infection. In spite of the name, H. influenzae do not cause influenza (the “flu”).

When the Haemophilus influenzae bacteria invade parts of the body that are normally free from germs, like spinal fluid or blood, this is known as “invasive disease.” Invasive disease is usually severe and can sometimes result in death.

Hib disease was once a leading cause of bacterial meningitis (swelling of the tissue covering the brain and spinal cord) among U.S. children younger than 5 years old. Every year about 20,000 children younger than five years old got invasive Hib disease and about 1,000 children died. More than half of the children who developed invasive Hib disease were younger than one year old. Due to the use of Hib vaccines, by 2014, fewer than 50 cases of Hib disease occurred each year in children younger than five years in the United States. Most cases of Hib disease today are in children who did not get a Hib vaccine or who have not been fully vaccinated.

The most common types of invasive disease caused by H. influenzae are:

Pneumonia* (lung infection)
Bacteremia (blood infection)
Meningitis (infection of the covering of the brain and spinal cord)
Epiglotittis (swelling of the windpipe that can cause breathing trouble)
Cellulitis (skin infection)
Infectious arthritis (inflammation of the joint)

Haemophilus influenzae can also be a common cause of ear infections in children and bronchitis in adults.

There are six identifiable types of H. influenzae bacteria (a through f) and other non-identifiable types (called nontypeable). The one people are most familiar with is Haemophilus influenzae type b, or Hib, that can be prevented with a vaccine. However, the vaccine does not protect against other types of the bacteria.

Hib vaccines are available that can help prevent Haemophilus influenzae type b or Hib disease. These vaccines do not provide protection against other types of Haemophilus influenzae disease. Haemophilus influenzae disease is any type of infection caused by Haemophilus influenzae bacteria.

Hib (Haemophilus influenzae type b) vaccination is recommended for all children younger than 5 years old in the United States, and the vaccine is usually given to babies starting at 2 months old. In certain situations, people at increased risk for invasive Hib disease who are fully vaccinated need more doses of a Hib vaccine. Unimmunized older children and adults with certain medical conditions should also get a Hib vaccine.

Talk with your or your child’s healthcare professional if you have questions about Hib vaccines.

What Types of Hib Vaccine Are There ?

There are 4 Haemophilus influenzae type b (Hib) vaccines licensed for use in the United States by the Food and Drug Administration (FDA), 1 of which is combined with vaccines for other diseases. Your child will get either 2 or 3 primary doses, depending on which vaccine is used, and a booster dose. The first primary dose can be given as early as 6 weeks. Any of the Hib-only vaccines can also be used for older children and adults that need Hib vaccination.

Hib-only Vaccines

PedvaxHIB®: It is given in a two-dose primary series plus one booster dose to children who are 2 through 15 months old.
ActHIB®: It is given in a three-dose primary series plus one booster dose to children who are 2 through 15 months old.
Hiberix®: It is given in a three-dose primary series plus one booster dose to children who are 2 months through 15 months old.

Combination Vaccines

A combination vaccine is when two or more vaccines are given in a single shot in order to decrease the number of shots given.

Pentacel®: It is given as a three-dose primary series plus one booster dose to children who are 2 through 18 months old to protect against Hib disease, diphtheria, tetanus, pertussis (whooping cough), and polio.

Who Should Get a Hib Vaccine ?

CDC recommends Haemophilus influenzae type b (Hib) vaccination for all children younger than 5 years old. Older children and adults usually do not need a Hib vaccine. Below is more information about when Hib vaccines are recommended, as well as information on who should not get Hib vaccines.

Talk to your or your child’s healthcare professional about what is best for your specific situation.

Young Children

Children younger than 5 years old need a primary series of two or three doses, depending on the brand used, and a booster dose of a Hib vaccine. Doses are recommended at the following ages:

2 months
4 months
6 months (if needed; depends on brand)
12 through 15 months

Older Children and Adults

Older children and adults usually do not need a Hib vaccine. However, some people who are fully vaccinated are at increased risk for invasive Hib disease and need additional doses. Unimmunized older children and adults with certain medical conditions should also get a Hib vaccine. Talk to your or your child’s healthcare professional about what is best for your specific situation.

Who Should Not Get Hib Vaccination ?

Because of age or health conditions, some people should not get certain vaccines or should wait before getting them. Read the guidelines below and ask your or your child’s healthcare professional for more information.

A Hib vaccine should not be given to babies younger than 6 weeks old.

In addition, tell the person who is giving you or your child a Hib vaccine if:

You or your child have had a life-threatening allergic reaction or have a severe allergy.

Anyone who has ever had a life-threatening allergic reaction after a previous dose of a Hib vaccine, or has a severe allergy to any part of this vaccine, should not get a Hib vaccine. Your or your child’s healthcare professional can tell you about each vaccine’s ingredients.

You or your child are not feeling well.

People who have a mild illness, such as a cold, can probably get the vaccine. People who are moderately or severely ill should probably wait until they recover. Your or your child’s healthcare professional can advise you.

Hib vaccine side-effects

With any medicine, including vaccines, there is a chance of side effects. These are usually mild and go away on their own. Serious reactions are also possible but are rare.

Most people who get Hib vaccine do not have any problems with it.

Mild Problems following Hib vaccine:

redness, warmth, or swelling where the shot was given
fever

These problems are uncommon. If they occur, they usually begin soon after the shot and last 2 or 3 days.

Problems that could happen after any vaccine:

Any medication can cause a severe allergic reaction. Such reactions from a vaccine are very rare, estimated at fewer than 1 in a million doses, and would happen within a few minutes to a few hours after the vaccination.

As with any medicine, there is a very remote chance of a vaccine causing a serious injury or death.

Older children, adolescents, and adults might also experience these problems after any vaccine:

People sometimes faint after a medical procedure, including vaccination. Sitting or lying down for about 15 minutes can help prevent fainting, and injuries caused by a fall. Tell your doctor if you feel dizzy, or have vision changes or ringing in the ears.
Some people get severe pain in the shoulder and have difficulty moving the arm where a shot was given. This happens very rarely.

How Well Do Hib Vaccines Work ?

Vaccines that help protect against Haemophilus influenzae type b (Hib) disease work well, but cannot prevent all cases.

Studies show that nearly all (between 93 and 100 out of 100) children are protected against invasive Hib disease after receiving a 2- or 3-dose primary series of Hib vaccine.
After receiving the primary series, antibody levels decrease and a booster dose is needed for children between 12 and 15 months old to maintain protection during early childhood.

HPV vaccine

What is HPV

Human papillomavirus (HPV) is a very common virus that can lead to cancer. Nearly 80 million people—about one in four—are currently infected with HPV in the United States. About 14 million people, including teens, become infected with HPV each year.

Over 30,000 people in the United States each year are affected by a cancer caused by HPV infection. While there is screening available for cervical cancer for women, there is no screening for the other cancers caused by HPV infection, like cancers of the mouth/throat, anus/rectum, penis, vagina, or vulva.

HPV vaccination provides safe, effective, and lasting protection against the HPV infections that most commonly cause cancer.

HPV Vaccine

What Types of HPV Vaccines Are There ?

Two HPV vaccines have been licensed by the U.S. Food and Drug Administration (FDA).

Gardasil (Merck) is a quadrivalent HPV vaccine (4vHPV) that protects against HPV types 6, 11, 16, and 18.
Gardasil-9 (Merck) is a nine-valent HPV vaccine (9vHPV) that protects against HPV types 6, 11, 16, 18, 31, 45, 52, and 58.

All two HPV vaccines protect against the two HPV types, 16 and 18, that cause most HPV cancers.

Who Should Get HPV Vaccine ?

HPV vaccination is recommended for preteen girls and boys at age 11 or 12 years. All preteens need HPV vaccination so they can be protected from HPV infections that cause cancer.

Teens and young adults who didn’t start or finish the HPV vaccine series also need HPV vaccination.
Teens and young women can get HPV vaccine until they are 27 years old and young men should get HPV vaccine until they are 22 years old.
Teens and young men who have sex with other men or who have weakened immune systems should get HPV vaccine until they are 27.
Transgender individuals should also get HPV vaccine until they are 27.

CDC recommends that 11- to 12-year-olds receive two doses of HPV vaccine at least six months apart to protect against cancers caused by human papillomavirus (HPV) infections.

The first dose is routinely recommended at 11-12 years old.
The second dose of the vaccine should be administered 6 to 12 months after the first dose.
Vaccination with the two-dose series can be started at age 9 and through age 14.

Teens and young adults who start the series later, at ages 15 through 26 years, need three doses of HPV vaccine to protect against cancer-causing HPV infection.

Adolescents aged 9 through 14 years who have already received two doses of HPV vaccine less than 5 months apart, will require a third dose.
Three doses are recommended for people with weakened immune systems aged 9-26 years.

Who Should Not Get HPV Vaccine ?

Tell your doctor about any severe allergies. Some people should not get some HPV vaccines, including:

People who have ever had a life-threatening allergic reaction to any ingredient of an HPV vaccine, or to a previous dose of HPV vaccine.
People who have an allergy to yeast (Gardasil and Gardasil 9).

HPV vaccines are safe for children who are mildly ill – for example, with a low-grade fever of less than 101 degrees, a cold, runny nose, or cough. People with a moderate or severe illness should wait until they are better.

How Well Do These HPV Vaccines Work ?

HPV vaccination works extremely well. Clinical trials showed the vaccines provided close to 100% protection against precancers and, for Gardasil and Gardasil 9, genital warts.

Since the vaccine was first recommended in 2006, there has been a significant reduction in HPV infections.
Research has also shown that fewer teens and young adults are getting genital warts.
In other countries such as Australia where there is higher HPV vaccination coverage, HPV vaccine has also reduced the number of cases of precancers of the cervix in young women in that country.
Also, genital warts have decreased dramatically in young adults in Australia since the HPV vaccine was introduced.

HPV vaccine offers long-lasting protection against HPV infection and HPV disease

10 years of data show that HPV vaccination provides long-lasting protection.
There is no evidence to suggest that HPV vaccine loses the ability to provide protection over time.

HPV Vaccine Side Effects

HPV–Gardasil-9 vaccine side-effects

Human Papillomavirus Gardasil-9 vaccine side effects

With any medicine, including vaccines, there is a chance of side effects. These are usually mild and go away on their own, but serious reactions are also possible.

Most people who get HPV vaccine do not have any serious problems with it.

Mild or moderate problems following HPV vaccine:

Reactions in the arm where the shot was given:
- Soreness (about 9 people in 10)
- Redness or swelling (about 1 person in 3)

Fever:

Mild (100°F) (about 1 person in 10)
Moderate (102°F) (about 1 person in 65)

Other problems:

Headache (about 1 person in 3)
Muscle or joint pain.

Problems that could happen after any injected vaccine:

People sometimes faint after a medical procedure, including vaccination. Sitting or lying down for about 15 minutes can help prevent fainting and injuries caused by a fall. Tell your doctor if you feel dizzy, or have vision changes or ringing in the ears.
Some people get severe pain in the shoulder and have difficulty moving the arm where a shot was given. This happens very rarely.
Any medication can cause a severe allergic reaction. Such reactions from a vaccine are very rare, estimated at about 1 in a million doses, and would happen within a few minutes to a few hours after the vaccination.

As with any medicine, there is a very remote chance of a vaccine causing a serious injury or death.

Meningococcal vaccine

What is Meningococcal Disease

Meningococcal disease can refer to any illness caused by the type of bacteria called Neisseria meningitidis, also known as meningococcus ¹⁶. These illnesses are often severe and can be deadly. They include infections of the lining of the brain and spinal cord (meningitis) and bloodstream infections (bacteremia or septicemia).

People spread meningococcal bacteria to other people by sharing respiratory and throat secretions (saliva or spit). Generally, it takes close (for example, coughing or kissing) or lengthy contact to spread these bacteria. Fortunately, they are not as contagious as germs that cause the common cold or the flu. People do not catch them through casual contact or by breathing air where someone with meningococcal disease has been.

Sometimes the bacteria spread to people who have had close or lengthy contact with a patient with meningococcal disease. Those at increased risk of getting sick include:

People who live with the patient
Anyone with direct contact with the patient’s oral secretions, such as a boyfriend or girlfriend

Close contacts of someone with meningococcal disease should receive antibiotics to help prevent them from getting the disease. This is known as prophylaxis. Health departments investigate each case of meningococcal disease to identify all close contacts and make sure they receive prophylaxis. This does not mean that the contacts have the disease; it is to prevent it. People who are not a close contact of a patient with meningococcal disease do not need prophylaxis.

Doctors treat meningococcal disease with antibiotics, but quick medical attention is extremely important. Keeping up to date with recommended vaccines is the best defense against meningococcal disease.

About 1 in 10 people have Neisseria meningitidis bacteria in the back of their nose and throat with no signs or symptoms of disease; this is called being ‘a carrier’. But sometimes the Neisseria meningitidis bacteria invade the body and cause certain illnesses, which are known as meningococcal disease.

There are five serogroups (types) of Neisseria meningitidis — A, B, C, W, and Y — that cause most disease worldwide. Three of these serogroups (B, C, and Y) cause most of the illness seen in the United States.

Vaccines are available that can help prevent meningococcal disease, which is any type of illness caused by Neisseria meningitidis bacteria. There are two types of meningococcal vaccines available in the United States:

Meningococcal conjugate vaccines (Menactra® and Menveo®)
Serogroup B meningococcal vaccines (Bexsero® and Trumenba®)

All 11 to 12 year olds should be vaccinated with a meningococcal conjugate vaccine. A booster dose is recommended at age 16 years. Teens and young adults (16 through 23 year olds) also may be vaccinated with a serogroup B meningococcal vaccine. In certain situations, other children and adults could be recommended to get meningococcal vaccines.

Talk with your or your child’s healthcare professional if you have questions about meningococcal vaccines.

Meningococcal vaccine

CDC recommends vaccination with a meningococcal conjugate vaccine for all preteens and teens at 11 to 12 years old, with a booster dose at 16 years old. Teens and young adults (16 through 23 year olds) also may be vaccinated with a serogroup B meningococcal vaccine.

What Types of Meningococcal Vaccines Are There ?

There are two types of meningococcal vaccines available in the United States:

Conjugate vaccines (Menactra® and Menveo®). Conjugate: A type of vaccine that joins a protein to part of the bacteria to improve the protection the vaccine provides.
Serogroup B (recombinant) vaccines (Bexsero® and Trumenba®). Recombinant: A type of vaccine where proteins from certain bacteria are used to help the body build protection against that germ.

Meningococcal Conjugate Vaccines

Menactra®: Two doses are given to preteens and teens. It is also given to certain people at increased risk of meningococcal disease. It helps protect against four types of the bacteria that cause meningococcal disease (serogroups A, C, W, and Y).
Menveo®: Two doses are given to preteens and teens. It is also given to certain people at increased risk of meningococcal disease. It helps protect against four types of the bacteria that cause meningococcal disease (serogroups A, C, W, and Y).

Serogroup B (Recombinant) Meningococcal Vaccines

Bexsero®: It is given as a two-dose series to people 16 through 23 years old who are not at increased risk of meningococcal disease. It is also given as a two-dose series to people 10 years or older at increased risk of meningococcal disease. It helps protect against one type of the bacteria that causes meningococcal disease (serogroup B).
Trumenba®: It is given as a two-dose series to people 16 through 23 years old who are not at increased risk of meningococcal disease. It is given as a three-dose series to people 10 years or older at increased risk of meningococcal disease. It helps protect against one type of the bacteria that causes meningococcal disease (serogroup B).

Who Should Get Meningococcal Vaccines ?

CDC recommends vaccination with meningococcal conjugate vaccine for all preteens and teens. In certain situations, other children and adults could be recommended to get meningococcal vaccines. Below is more information about which meningococcal vaccines are recommended for people by age, as well as information on who should not get meningococcal vaccines.

Talk to your or your child’s healthcare professional about what is best for your specific situation.

Preteens and Teens

There are two types of meningococcal vaccines for preteens and teens:

Meningococcal conjugate vaccines (Menactra® or Menveo®)
Serogroup B meningococcal vaccines (Bexsero® or Trumenba®)

All 11 to 12 year olds should be vaccinated with a meningococcal conjugate vaccine, with a booster dose given at 16 years old. All teens may also be vaccinated with a serogroup B meningococcal vaccine, preferably at 16 through 18 years old.

In addition to a meningococcal conjugate vaccine, certain preteens and teens should get a serogroup B meningococcal vaccine if they:

Have a rare type of disorder (complement component deficiency)
Are taking the medicine called Soliris®
Have a damaged spleen or their spleen has been removed
Are part of a population identified to be at increased risk because of a serogroup B meningococcal disease outbreak

Babies and Children

CDC recommends a meningococcal conjugate vaccine (Menactra® or Menveo®) for children who are between 2 months and 10 years old, if they:

Have a rare type of disorder (complement component deficiency)
Are taking the medicine called Soliris®
Have a damaged spleen or their spleen has been removed
Have HIV
Are traveling to or residing in countries in which the disease is common
Are part of a population identified to be at increased risk because of a serogroup A, C, W, or Y meningococcal disease outbreak

Talk to your child’s doctor to find out if, and when, they will need booster shots.

CDC recommends a serogroup B meningococcal vaccine (Bexsero® or Trumenba®) for children 10 years or older if they:

Have a rare type of disorder (complement component deficiency)
Are taking a medicine called Soliris®
Have a damaged spleen or their spleen has been removed
Are part of a population identified to be at increased risk because of a serogroup B meningococcal disease outbreak

Adults

Meningococcal vaccines are recommended for certain groups of adults at increased risk for meningococcal disease. Each meningococcal vaccine is listed below with which groups of adults are recommended to get it.

Meningococcal Conjugate Vaccine Recommendations

Adults should get a meningococcal conjugate vaccine (Menactra® or Menveo®) if they:

Have a rare type of disorder (complement component deficiency)
Are taking a medicine called Soliris®
Have a damaged spleen or their spleen has been removed
Have HIV
Are a microbiologist who is routinely exposed to Neisseria meningitidis
Are traveling to or residing in countries in which the disease is common
Are part of a population identified to be at increased risk because of a serogroup A, C, W, or Y meningococcal disease outbreak
Are not up to date with this vaccine and are a first-year college student living in a residence hall
Are a military recruit

Talk to your doctor to find out if, and when, you will need booster shots.

Serogroup B Meningococcal Vaccine Recommendations

Adults should get a serogroup B meningococcal vaccine (Bexsero® or Trumenba®) if they:

Have a rare type of disorder (complement component deficiency)
Are taking a medicine called Soliris®
Have a damaged spleen or their spleen has been removed
Are a microbiologist who is routinely exposed to Neisseria meningitidis
Are part of a population identified to be at increased risk because of a serogroup B meningococcal disease outbreak

Who Should Not Get Meningococcal Vaccines ?

Tell the person who is giving you or your child a meningococcal vaccine if:

You or your child have had a life-threatening allergic reaction or have a severe allergy.

Anyone who has ever had a life-threatening allergic reaction after a previous dose of a meningococcal vaccine should not get another dose of that vaccine.
Anyone who has a severe allergy to any part of these vaccines should not get another dose of that vaccine. Your child’s healthcare professional can tell you about the vaccine’s ingredients.

You are pregnant or breastfeeding.

Meningococcal conjugate vaccines may be given to pregnant women who are at increased risk for serogroup A, C, W, or Y meningococcal disease.
Serogroup B meningococcal vaccines should only be given to pregnant or breastfeeding women who are at increased risk for serogroup B meningococcal disease who decide, after talking with a doctor, that the benefits of getting the vaccine outweigh the risk.

You or your child are not feeling well.

People who have a mild illness, such as a cold, can probably get the vaccine. People who are moderately or severely ill should probably wait until they recover. Your or your child’s healthcare professional can advise you.

How Well Do These Meningococcal Vaccines Work ?

Vaccines that help protect against meningococcal disease work well, but cannot prevent all cases.

In studies demonstrating the efficacy of meningococcal conjugate vaccines:

Menactra® in preteens and teens: Between 8 and 9 people out of every 10 vaccinated had a protective immune response one month after completing the series
Menactra® in adults: Between 7 and 9 people out of every 10 vaccinated had a protective immune response one month after completing the series
Menveo® in preteens and teens: Between 7 and 9 people out of every 10 vaccinated had a protective immune response one month after completing the series
Menveo® in adults: Between 7 and 9 people out of every 10 vaccinated had a protective immune response one month after completing the series

In studies demonstrating the efficacy of serogroup B meningococcal vaccines:

Besexero® in preteens, teens, and young adults: Between 6 and 9 people out of every 10 vaccinated had a protective immune response one month after completing the series
Trumenba® in preteens, teens, and young adults: 8 people out of every 10 vaccinated had a protective immune response one month after completing the series.

Meningococcal ACWY vaccine side-effects

With any medicine, including vaccines, there is a chance of side effects. These are usually mild and go away on their own within a few days, but serious reactions are also possible.

As many as half of the people who get meningococcal ACWY vaccine have mild problems following vaccination, such as redness or soreness where the shot was given. If these problems occur, they usually last for 1 or 2 days. They are more common after MenACWY than after MPSV4.

A small percentage of people who receive the vaccine develop a mild fever.

Mild Problems

Meningococcal Conjugate Vaccines

Mild problems following meningococcal conjugate vaccination can include:

Reactions where the shot was given
- Redness
- Pain
Fever

If these problems occur, they usually last for 1 or 2 days.

Serogroup B Meningococcal Vaccines

Mild problems following a serogroup B meningococcal vaccination can include:

Reactions where the shot was given
- Soreness
- Redness
- Swelling
Feeling tired
Headache
Muscle or joint pain
Fever or chills
Nausea or diarrhea

If these problems occur, they can last up to 3 to 7 days.

Problems that could happen after any injected vaccine:

People sometimes faint after a medical procedure, including vaccination. Sitting or lying down for about 15 minutes can help prevent fainting, and injuries caused by a fall. Tell your doctor if you feel dizzy, or have vision changes or ringing in the ears.
Some people get severe pain in the shoulder and have difficulty moving the arm where a shot was given. This happens very rarely.
Any medication can cause a severe allergic reaction. Such reactions from a vaccine are very rare, estimated at about 1 in a million doses, and would happen within a few minutes to a few hours after the vaccination.

As with any medicine, there is a very remote chance of a vaccine causing a serious injury or death.

MMR Vaccine

What is MMR (measles, mumps and rubella) disease ?

Measles is a very contagious disease caused by a virus. It spreads through the air when an infected person coughs or sneezes. Measles starts with fever. Soon after, it causes a cough, runny nose, and red eyes. Then a rash of tiny, red spots breaks out. It starts at the head and spreads to the rest of the body.

Measles can be prevented with MMR vaccine. The vaccine protects against three diseases: measles, mumps, and rubella. CDC recommends children get two doses of MMR vaccine, starting with the first dose at 12 through 15 months of age, and the second dose at 4 through 6 years of age. Teens and adults should also be up to date on their MMR vaccination.

The MMR vaccine is very safe and effective. Two doses of MMR vaccine are about 97% effective at preventing measles; one dose is about 93% effective.

Children may also get MMRV vaccine, which protects against measles, mumps, rubella, and varicella (chickenpox). This vaccine is only licensed for use in children who are 12 months through 12 years of age.

Before the measles vaccination program started in 1963, an estimated 3 to 4 million people got measles each year in the United States. Of these, approximately 500,000 cases were reported each year to CDC; of these, 400 to 500 died, 48,000 were hospitalized, and 1,000 developed encephalitis (brain swelling) from measles. Since then, widespread use of measles vaccine has led to a greater than 99% reduction in measles cases compared with the pre-vaccine era. However, measles is still common in other countries. Unvaccinated people continue to get measles while abroad and bring the disease into the United States and spread it to others.

CDC recommends that people get MMR vaccine to protect against measles, mumps, and rubella. Children should get two doses of MMR vaccine, starting with the first dose at 12 to 15 months of age, and the second dose at 4 through 6 years of age. Teens and adults also should also be up to date on their MMR vaccination.

Children may also get MMRV (Measles, Mumps, Rubella & Varicellavaccine, which protects against measles, mumps, rubella, and varicella (chickenpox). This vaccine is only licensed for use in children who are 12 months through 12 years of age.

MMR Vaccine

MMRV vaccine protects against four diseases: measles, mumps, rubella, and varicella (chickenpox). This vaccine is only licensed for use in children 12 months through 12 years of age.

CDC recommends that children get one dose of MMRV (Measles, Mumps, Rubella & Varicella) vaccine at 12 through 15 months of age, and the second dose at 4 through 6 years of age. A doctor can help parents decide whether to use this vaccine or MMR vaccine.

MMRV is given by shot and may be given at the same time as other vaccines.

Who Should Get MMR Vaccine ?

Children

CDC recommends all children get two doses of MMR (measles-mumps-rubella) vaccine, starting with the first dose at 12 through 15 months of age, and the second dose at 4 through 6 years of age. Children can receive the second dose earlier as long as it is at least 28 days after the first dose.

MMR vaccine is given later than some other childhood vaccines because antibodies transferred from the mother to the baby can provide some protection from disease and make the MMR vaccine less effective until about 1 year of age.

MMRV (Measles, Mumps, Rubella & Varicella) vaccine, which protects against measles, mumps, rubella, and varicella (chickenpox), is only licensed for use in children who are 12 months through 12 years of age.

Students at post-high school educational institutions

Students at post-high school educational institutions who do not have evidence of immunity need two doses of MMR vaccine, separated by at least 28 days.

Adults

Adults who do not have evidence of immunity should get at least one dose of MMR vaccine.

International travelers

People 6 months of age and older who will be traveling internationally should be protected against measles. Before any international travel—

Infants 6 through 11 months of age should receive one dose of MMR vaccine. Infants who get one dose of MMR vaccine before their first birthday should get two more doses (one dose at 12 through 15 months of age and another dose separated by at least 28 days).
Children 12 months of age and older should receive two doses of MMR vaccine, separated by at least 28 days.
Teenagers and adults who do not have evidence of immunity against measles should get two doses of MMR vaccine separated by at least 28 days.

Healthcare personnel

Healthcare personnel should have documented evidence of immunity, according to the recommendations of the Advisory Committee on Immunization Practices. Healthcare personnel without evidence of immunity should get two doses of MMR vaccine, separated by at least 28 days.

Women of Childbearing Age

Women of childbearing age should check with their doctor to make sure they are vaccinated before they get pregnant. Women of childbearing age who do not have evidence of immunity should get at least one dose of MMR vaccine.

It is safe for breastfeeding women to receive MMR vaccination. Breastfeeding does not interfere with the response to MMR vaccine, and the baby will not be affected by the vaccine through breast milk.

Who Should Not Get MMR Vaccine ?

Some people should not get MMR vaccine or should wait.

Anyone who has ever had a life-threatening allergic reaction to the antibiotic neomycin, or any other component of MMR vaccine, should not get the vaccine. Tell your doctor if you have any severe allergies.
Anyone who had a life-threatening allergic reaction to a previous dose of MMR or MMRV vaccine should not get another dose.
Some people who are sick at the time the shot is scheduled may be advised to wait until they recover before getting MMR vaccine.
Pregnant women should not get MMR vaccine. Pregnant women who need the vaccine should wait until after giving birth. Women should avoid getting pregnant for 4 weeks after vaccination with MMR vaccine.
Tell your doctor if the person getting the vaccine:
- Has HIV/AIDS, or another disease that affects the immune system
- Is being treated with drugs that affect the immune system, such as steroids
- Has any kind of cancer
- Is being treated for cancer with radiation or drugs
- Has ever had a low platelet count (a blood disorder)
- Has gotten another vaccine within the past 4 weeks
- Has recently had a transfusion or received other blood products
- Any of these might be a reason to not get the vaccine, or delay vaccination until later.

A minor illness, such as a cold or chickenpox, should not delay anyone from receiving the benefits of MMR or any other vaccine. In addition, it is safe for people around a pregnant woman to be vaccinated. Measles, mumps, and rubella vaccine viruses are not transmitted from the vaccinated person, so a recently vaccinated person would not pose a risk to a pregnant woman.

Who Does Not Need MMR Vaccine ?

You do not need measles, mumps, and rubella (MMR) vaccine if you meet any of these criteria for evidence of immunity:

You have written documentation of adequate vaccination:
- at least one dose of a measles-, mumps-, and rubella-containing vaccine administered on or after the first birthday for preschool-age children and adults not at high risk for exposure and transmission
- two doses of measles- and mumps-containing vaccine for school-age children and adults at high risk for exposure and transmission, including college students, healthcare personnel, and international travelers
You had blood tests that show you are immune to measles, mumps, and rubella.
You have laboratory confirmation of past measles, mumps, or rubella infection.
You were born before 1957.*

If you do not have evidence of immunity against measles, mumps, and rubella, talk with your doctor about getting vaccinated. If you’re unsure whether you’ve been vaccinated, you should first try to find your vaccination records. If you do not have written documentation of MMR vaccine, you should get vaccinated. The MMR vaccine is safe, and there is no harm in getting another dose if you may already be immune to measles, mumps, or rubella.

If you received a measles vaccine in the 1960s, you may not need to be revaccinated. People who have documentation of receiving LIVE measles vaccine in the 1960s do not need to be revaccinated. People who were vaccinated prior to 1968 with either inactivated (killed) measles vaccine or measles vaccine of unknown type should be revaccinated with at least one dose of live attenuated measles vaccine. This recommendation is intended to protect those who may have received killed measles vaccine, which was available in 1963-1967 and was not effective.

* Birth before 1957 provides only presumptive evidence for measles, mumps, and rubella. Before vaccines were available, nearly everyone was infected with measles, mumps, and rubella viruses during childhood. The majority of people born before 1957 are likely to have been infected naturally and therefore are presumed to be protected against measles, mumps, and rubella.

MMR vaccine side-effects

A vaccine, like any medicine, is capable of causing serious problems, such as severe allergic reactions.

The risk of MMR vaccine causing serious harm, or death, is extremely small.

Getting MMR vaccine is much safer than getting measles, mumps or rubella.

Most people who get MMR vaccine do not have any serious problems with it.

Mild problems

Fever (up to 1 person out of 6)
Mild rash (about 1 person out of 20)
Swelling of glands in the cheeks or neck (about 1 person out of 75)

If these problems occur, it is usually within 6-14 days after the shot. They occur less often after the second dose.

Moderate problems

Seizure (jerking or staring) caused by fever (about 1 out of 3,000 doses)
Temporary pain and stiffness in the joints, mostly in teenage or adult women (up to 1 out of 4)
Temporary low platelet count, which can cause a bleeding disorder (about 1 out of 30,000 doses)

Severe problems (very rare)

Serious allergic reaction (less than 1 out of a million doses)
Several other severe problems have been reported after a child gets MMR vaccine, including:
Deafness
Long-term seizures, coma, or lowered consciousness
Permanent brain damage

These are so rare that it is hard to tell whether they are caused by the vaccine.

MMRV (Measles, Mumps, Rubella, and Varicella) vaccine side-effects

A vaccine, like any medicine, is capable of causing serious problems, such as severe allergic reactions. The risk of MMRV vaccine causing serious harm, or death, is extremely small.

Getting MMRV vaccine is much safer than getting measles, mumps, rubella, or chickenpox.

Most children who get MMRV vaccine do not have any problems with it.

Mild problems

Fever (about 1 child out of 5).
Mild rash (about 1 child out of 20).
Swelling of glands in the cheeks or neck (rare).

If these problems happen, it is usually within 5-12 days after the first dose. They happen less often after the second dose.

Moderate problems

Seizure caused by fever (about 1 child in 1,250 who get MMRV), usually 5-12 days after the first dose. They happen less often when MMR and varicella vaccines are given at the same visit as separate shots (about 1 child in 2,500 who get these two vaccines), and rarely after a 2nd dose of MMRV.
Temporary low platelet count, which can cause a bleeding disorder (about 1 child out of 40,000).

Severe problems (very rare)

Several severe problems have been reported following MMR vaccine, and might also happen after MMRV. These include severe allergic reactions (fewer than 4 per million), and problems such as:

Deafness.
Long-term seizures, coma, lowered consciousness.
Permanent brain damage.

Because these problems occur so rarely, we can’t be sure whether they are caused by the vaccine or not.

Pneumococcal Vaccine

What is Pneumococcal disease

Pneumococcal disease is an infection caused by Streptococcus pneumoniae bacteria, sometimes referred to as pneumococcus. Pneumococcus is the most common cause of bloodstream infections, pneumonia, meningitis, and middle ear infections in young children.

Doctors consider some of these infections “invasive.” Invasive disease means that germs invade parts of the body that are normally free from germs. For example, pneumococcal bacteria can invade the bloodstream, causing bacteremia, and the tissues and fluids covering the brain and spinal cord, causing meningitis. When this happens, disease is usually very severe, requiring treatment in a hospital and even causing death in some cases.

Children younger than 2 years old and adults 65 years or older are among those most at risk for disease. There are vaccines to prevent pneumococcal disease in children and adults.

There are two kinds of pneumococcal vaccines available in the United States:

Pneumococcal conjugate vaccine (PCV13 or Prevnar 13®) protects against 13 types of pneumococcal bacteria.
Pneumococcal polysaccharide vaccine (PPSV23 or Pneumovax®) protects against 23 types of pneumococcal bacteria.

Pneumococcal conjugate vaccine is recommended for all babies and children younger than 2 years old, all adults 65 years or older, and people 2 through 64 years old with certain medical conditions. Pneumococcal polysaccharide vaccine is recommended for all adults 65 years or older, people 2 through 64 years old who are at increased risk for disease due to certain medical conditions, and adults 19 through 64 years old who smoke cigarettes.

Talk with your or your child’s healthcare professional if you have questions about pneumococcal vaccines.

Pneumococcal Vaccine

What Types of Pneumococcal Vaccines Are There ?

There are two pneumococcal vaccines that are licensed for use in the United States by the Food and Drug Administration (FDA):

Pneumococcal conjugate vaccine (PCV13 or Prevnar 13®). Conjugate: A type of vaccine that joins a protein to part of the bacteria to improve the protection the vaccine provides.
Pneumococcal polysaccharide vaccine (PPSV23 or Pneumovax23®). Polysaccharide: A type of vaccine that is made to look like the surface of certain bacteria in order to help the body build protection against that germ.

Pneumococcal Conjugate Vaccine

Prevnar 13®: This vaccine is given in a three-dose primary series starting at 2 months of age plus one booster dose at 12 through 15 months of age. Children who begin vaccination after 6 months of age will receive fewer doses. Adults who are recommended to receive it only need a single dose. The vaccine helps protect against the 13 types of pneumococcal bacteria that are the most common causes of serious infections in children and adults. It can also help prevent some ear infections.

Pneumococcal Polysaccharide Vaccine

Pneumovax23®: This vaccine is given as a single dose to people who are recommended to receive it. One or two booster doses are recommended for some people. This vaccine helps protect against 23 types of pneumococcal bacteria.

Who Should Get Pneumococcal Vaccines ?

CDC recommends pneumococcal vaccination for all babies and children younger than 2 years old and all adults 65 years or older. In certain situations, other children and adults should also get pneumococcal vaccines. Below is more information about who should and should not get each type of pneumococcal vaccine.

Talk to your or your child’s healthcare professional about what is best for your specific situation.

PCV13 for Infants, Children, and Adults

The pneumococcal conjugate vaccine (PCV13 or Prevnar 13®) protects against 13 types of pneumococcal bacteria.

Before the vaccine, there were about 700 cases of meningitis, 13,000 bloodstream infections, and 200 deaths from pneumococcal disease each year among children younger than 5 years old. After children started getting this vaccine, these numbers dropped quickly.
doctor vaccinating patient

CDC recommends vaccination with the pneumococcal conjugate vaccine (PCV13 or Prevnar 13®) for

All babies and children younger than 2 years old
All adults 65 years or older
People 2 through 64 years old who are at increased risk for disease due to certain medical conditions

PPSV23 for Children and Adults

CDC recommends vaccination with the pneumococcal polysaccharide vaccine (PPSV23 or Pneumovax23®) for:

All adults 65 years or older
People 2 through 64 years old who are at increased risk for disease due to certain medical conditions
Adults 19 through 64 years old who smoke cigarettes.

Who Should Not Get These Vaccines ?

Pneumococcal Conjugate Vaccine

Tell the person who is giving you or your child a pneumococcal conjugate vaccine if:

You or your child have had a life-threatening allergic reaction or have a severe allergy.

Anyone who has had a life-threatening allergic reaction to a dose of this vaccine, to an earlier pneumococcal conjugate vaccine called PCV7 (or Prevnar®), or to any vaccine containing diphtheria toxoid (for example, DTaP) should not get PCV13.
Anyone with a severe allergy to any component of PCV13 should not get the vaccine. Your or your child’s healthcare professional can tell you about each vaccine’s ingredients.

You or your child are not feeling well.

People who have a mild illness, such as a cold, can probably get the vaccine. People who are moderately or severely ill should probably wait until they recover. Your or your child’s healthcare professional can advise you.

You are pregnant.

There is no evidence on the safety of PCV13 use during pregnancy. As a precaution, women who need the vaccine should be vaccinated before becoming pregnant, if possible.

Pneumococcal Polysaccharide Vaccine

Children younger than 2 years old should not get this vaccine. In addition, tell the person who is giving you or your child a pneumococcal polysaccharide vaccine if:
You or your child have had a life-threatening allergic reaction or have a severe allergy.

Anyone who has had a life-threatening allergic reaction to PPSV23 should not get another dose.
Anyone who has a severe allergy to any component of PPSV23 should not get it. Your or your child’s healthcare professional can tell you about each vaccine’s ingredients.

You or your child are not feeling well.

You are pregnant.

There is no evidence that PPSV23 is harmful to either a pregnant woman or to her baby. However, as a precaution, women who need the vaccine should be vaccinated before becoming pregnant, if possible.

What Are the Possible Side Effects-Pneumococcal Vaccines ?

Most people who get a pneumococcal vaccine do not have any serious problems with it. With any medicine, including vaccines, there is a chance of side effects. These are usually mild and go away on their own within a few days, but serious reactions are also possible.

Mild Problems

Pneumococcal Conjugate Vaccine

Mild problems following pneumococcal conjugate vaccination can include:

Reactions where the shot was given
Redness
Swelling
Pain or tenderness
Fever
Loss of appetite
Fussiness (irritability)
Feeling tired
Headache
Chills

Young children who get pneumococcal conjugate vaccination along with inactivated flu vaccine at the same time may be at increased risk for seizures caused by fever. Ask your doctor for more information.

Pneumococcal Polysaccharide Vaccine

Mild problems following pneumococcal polysaccharide vaccination can include:

Reactions where the shot was given
Redness
Pain
Fever
Muscle aches

If these problems occur, they usually go away within about two days.

Polio Vaccine

What is Polio

Polio is an infectious disease caused by a virus that lives in the throat and intestinal tract. It is most often spread through person-to-person contact with the stool of an infected person and may also be spread through oral/nasal secretions. Polio used to be very common in the United States and caused severe illness in thousands of people each year before polio vaccine was introduced in 1955. Most people infected with the polio virus have no symptoms; however, for the less than 1% who develop paralysis it may result in permanent disability and even death.

There are two types of vaccine that protect against polio: inactivated poliovirus vaccine (IPV) and oral poliovirus vaccine (OPV). IPV is given as an injection in the leg or arm, depending on the patient’s age. Polio vaccine may be given at the same time as other vaccines. Most people should get polio vaccine when they are children. Children get 4 doses of IPV at these ages: 2 months, 4 months, 6-18 months, and a booster dose at 4-6 years. OPV has not been used in the United States since 2000 but is still used in many parts of the world.

CDC recommends that children get polio vaccine to protect against polio, or poliomyelitis. Inactivated polio vaccine (IPV) is the only polio vaccine that has been given in the United States since 2000. IPV is given by shot in the leg or arm, depending on the patient’s age. Oral polio vaccine (OPV) is used in other countries.

CDC recommends that children get four doses of polio vaccine. They should get one dose at each of the following ages: 2 months old, 4 months old, 6 through 18 months old, and 4 through 6 years old.

Polio Vaccine

What are the Types of Polio Vaccine ?

Two types of vaccine that protect against polio, or poliomyelitis.

Inactivated poliovirus vaccine (IPV)

IPV is the only polio vaccine that has been used in the United States since 2000.
It is given by shot in the leg or arm, depending on the patient’s age.
Children should get four doses total, with one dose at each of the following ages:
- 2 months old,
- 4 months old,
- 6 through 18 months old, and
- 4 through 6 years old.

Oral poliovirus vaccine (OPV)

OPV was used in the United States before IPV was available in this country.
This vaccine is no longer licensed or available in the United States.
It is still used in many parts of the world.
Children receive doses of the vaccine by drops in the mouth.

Who Should Get Polio Vaccine ?

Infants and Children

Children in the United States should get inactivated polio vaccine (IPV) to protect against polio, or poliomyelitis. They should get four doses total, with one dose at each of the following ages:

2 months old
4 months old
6 through 18 months old
4 through 6 years old

Children who will be traveling to a country where the risk of getting polio is greater should complete the series before leaving for their trip. If a child cannot complete the routine series before leaving, an accelerated schedule is recommended as follows:

1 dose at age 6 weeks or older
a second dose 4 or more weeks after the first dose
a third dose 4 or more weeks after the second dose
a fourth dose 6 or more months after the third dose

If the accelerated schedule cannot be completed before leaving, the remaining doses should be given in the affected country, or upon returning home, at the intervals recommended in the accelerated schedule. In addition, children completing the accelerated schedule should still receive a dose of IPV at 4 years old or older, as long as it has been at least 6 months after the last dose.

Adults

Most adults do not need polio vaccine because they were already vaccinated as children. But three groups of adults are at higher risk and should consider polio vaccination in the following situations:

You are traveling to a country where the risk of getting polio is greater. Ask your healthcare provider for specific information on whether you need to be vaccinated.
You are working in a laboratory and handling specimens that might contain polioviruses.
You are a healthcare worker treating patients who could have polio or have close contact with a person who could be infected with poliovirus.

Adults in these three groups who have never been vaccinated against polio should get 3 doses of IPV:

The first dose at any time,
The second dose 1 to 2 months later,
The third dose 6 to 12 months after the second.

Adults in these three groups who have had 1 or 2 doses of polio vaccine in the past should get the remaining 1 or 2 doses. It doesn’t matter how long it has been since the earlier dose(s).

Adults who are at increased risk of exposure to poliovirus and who have previously completed a routine series of polio vaccine (IPV or OPV) can receive one lifetime booster dose of IPV.

Who Should Not Get Polio Vaccine ?

Tell the person who is giving the vaccine:

If the person getting the vaccine has any severe, life-threatening allergies.
If you ever had a life-threatening allergic reaction after a dose of IPV, or have a severe allergy to any part of this vaccine, you may be advised not to get vaccinated. Ask your health care provider if you want information about vaccine components.
If the person getting the vaccine is not feeling well.
If you have a mild illness, such as a cold, you can probably get the vaccine today. If you are moderately or severely ill, you should probably wait until you recover. Your doctor can advise you.

Polio vaccine side-effects

With any medicine, including vaccines, there is a chance of side effects. These are usually mild and go away on their own, but serious reactions are also possible.

Some people who get IPV get a sore spot where the shot was given. IPV has not been known to cause serious problems, and most people do not have any problems with it.

Other problems that could happen after this vaccine:

People sometimes faint after a medical procedure, including vaccination. Sitting or lying down for about 15 minutes can help prevent fainting and injuries caused by a fall. Tell your provider if you feel dizzy, or have vision changes or ringing in the ears.
Some people get shoulder pain that can be more severe and longer-lasting than the more routine soreness that can follow injections. This happens very rarely.
Any medication can cause a severe allergic reaction. Such reactions from a vaccine are very rare, estimated at about 1 in a million doses, and would happen within a few minutes to a few hours after the vaccination.

As with any medicine, there is a very remote chance of a vaccine causing a serious injury or death.

Rabies Vaccine

Rabies is a preventable viral disease of mammals most often transmitted through the bite of a rabid animal. The vast majority of rabies cases reported to the Centers for Disease Control and Prevention (CDC) each year occur in wild animals like raccoons, skunks, bats, and foxes.

Wash any wounds immediately. One of the most effective ways to decrease the chance for infection is to wash the wound thoroughly with soap and water.

See your doctor for attention for any trauma due to an animal attack before considering the need for rabies vaccination.

Your doctor, possibly in consultation with your state or local health department, will decide if you need a rabies vaccination. Decisions to start vaccination, known as postexposure prophylaxis (PEP), will be based on your type of exposure and the animal you were exposed to, as well as laboratory and surveillance information for the geographic area where the exposure occurred.

Rabies vaccine is given to people at increased risk of rabies to protect them if they are exposed. It can also prevent the disease if it is given to a person after they have been exposed.

Rabies vaccine is made from killed rabies virus. It cannot cause rabies.

Preexposure vaccination is recommended for persons in high-risk groups, such as veterinarians, animal handlers, and certain laboratory workers. Although preexposure vaccination does not eliminate the need for additional medical attention after a rabies exposure, it can decrease the number of vaccine doses needed, and it minimizes adverse reactions to multiple doses of vaccine.

Rabies vaccine side-effects

A vaccine, like any medicine, is capable of causing serious problems, such as severe allergic reactions. The risk of a vaccine causing serious harm, or death, is extremely small. Serious problems from rabies vaccine are very rare.

Mild problems

soreness, redness, swelling, or itching where the shot was given (30% – 74%)
headache, nausea, abdominal pain, muscle aches, dizziness (5% – 40%)

Moderate problems

hives, pain in the joints, fever (about 6% of booster doses)

Other nervous system disorders, such as Guillain Barré syndrome (GBS), have been reported after rabies vaccine, but this happens so rarely that it is not known whether they are related to the vaccine.

NOTE: Several brands of rabies vaccine are available in the United States, and reactions may vary between brands. Your provider can give you more information about a particular brand.

Smallpox Vaccine

After smallpox was eliminated from the world, routine vaccination against smallpox among the general public was stopped because it was no longer needed. However, because of concern that variola virus might be used as an agent of bioterrorism, the U.S. government has stockpiled enough smallpox vaccine to vaccinate everyone who would need it if a smallpox outbreak were to occur.

When there is NO smallpox outbreak, you should get the smallpox vaccine if you are a lab worker who works with virus that causes smallpox or other viruses that are similar to it.

If you need long-term protection, you may need to get booster vaccinations regularly. To stay protected from smallpox, you should get booster vaccinations every 3 years.

When there IS a smallpox outbreak, you should get the smallpox vaccine if you are directly exposed to smallpox virus. For example, if you had a prolonged face-to-face contact with someone who has smallpox.

If there is a smallpox outbreak, public health officials will say who else should get the vaccine. CDC works with federal, state, and local officials to prepare for a smallpox outbreak.

You can get additional information on smallpox vaccine here: ¹⁷

Typhoid Vaccine

What is Typhoid Fever ?

Typhoid fever is a life-threatening illness caused by the bacterium Salmonella Typhi. An estimated 5,700 cases occur each year in the United States. Most cases (up to 75%) are acquired while traveling internationally. Typhoid fever is still common in the developing world, where it affects about 21.5 million people each year.

If you are traveling to a country where typhoid (Salmonella serotype Typhi) is common, you should consider being vaccinated against typhoid. Visit a doctor or travel clinic to discuss your vaccination options.

Remember that you will need to complete your vaccination at least 1 week before you travel so that the vaccine has time to take effect. Typhoid vaccines lose effectiveness after several years; if you were vaccinated in the past, check with your doctor to see if it is time for a booster vaccination.

Typhoid Vaccine

Typhoid vaccination is not usually needed in the U.S. It is usually recommended only for international travelers going to developing countries where exposure to contaminated food or water is likely. If needed, there are currently two vaccines available in the United States. Please consult your doctor or travel clinic to determine which vaccine is right for you.

Typhoid vaccine side-effects

Like any medicine, a vaccine could cause a serious problem, such as a severe allergic reaction. The risk of typhoid vaccine causing serious harm, or death, is extremely small. Serious problems from either typhoid vaccine are very rare.

Inactivated typhoid vaccine (Shot)

Mild reactions

Fever (up to about 1 person in 100)
Headache (up to about 1 person in 30)
Redness or swelling at the site of the injection (up to about 1 person in 15)

Live typhoid vaccine (Oral)

Mild reactions

Fever or headache (up to about 1 person in 20)
Stomach pain, nausea, vomiting, rash (rare).

Varicella Vaccine

See Chickenpox vaccine above.

Yellow Fever Vaccine

What is Yellow Fever

Yellow fever is a serious disease caused by the yellow fever virus. Yellow fever virus is found in tropical and subtropical areas in South America and Africa. The virus is transmitted to people by the bite of an infected mosquito and cannot be spread directly from person-to-person. Yellow fever is a very rare cause of illness in U.S. travelers. Illness ranges in severity from a self-limited febrile illness to severe liver disease with bleeding.

Yellow fever disease is diagnosed based on symptoms, physical findings, laboratory testing, and travel history, including the possibility of exposure to infected mosquitoes. There is no specific treatment for yellow fever; care is based on symptoms. Steps to prevent yellow fever virus infection include using insect repellent, wearing protective clothing, and getting vaccinated.

Yellow fever vaccine can prevent yellow fever.

Yellow fever can cause:

Fever and flu-like illness
Jaundice (yellow skin or eyes)
Liver, kidney, respiratory, and other organ system failure
Vomiting blood
Death (20% – 50% of serious cases)

People with yellow fever disease usually have to be hospitalized.

Yellow fever vaccine is given only at approved vaccination centers. After receiving the vaccine, you should receive an International Certificate of Vaccination (yellow card) that has been validated by the vaccination center. The certificate becomes valid 10 days after vaccination and lasts for ten years. You will need this card as proof of vaccination to enter certain countries.

Another way to prevent yellow fever is to avoid mosquito bites by:

staying in well-screened or air-conditioned areas,
wearing clothes that cover most of your body,
using an effective insect repellent, such as those containing DEET.

Yellow Fever Vaccine

Yellow Fever Vaccine is Recommended for:

Persons nine months or older traveling to or living in a country that requires yellow fever vaccination for certain travelers. Check with your health care provider.
Persons nine months or older traveling to a country that does not require yellow fever vaccination, but is located in an area where the risk of yellow fever is known to exist. Check with your health care provider.
Information about known or probable infected areas is available from the World Health Organization, the Pan American Health Organization, and CDC.
If you continue to live or travel in yellow fever-endemic areas, you should receive a booster dose of yellow fever vaccine after 10 years. Yellow fever vaccine may be given at the same time as most other vaccines.

Consult your health department or visit CDC’s travel information website ¹⁸ to learn the travel requirements for different countries or to find the nearest approved vaccination center. Please make sure you discuss your travel itinerary with your doctor or nurse before you receive your yellow fever vaccination.

Who should not get yellow fever vaccine ?

Anyone with a severe (life-threatening) allergy to any component of the vaccine, including eggs, chicken proteins, or gelatin, or who has had a severe allergic reaction to a previous dose of yellow fever vaccine should not get yellow fever vaccine. Tell your doctor if you have any severe allergies.
Infants younger than 6 months of age should not get the vaccine.
Tell your doctor if:
- You have HIV/AIDS or another disease that affects the immune system.
- Your immune system is weakened as a result of cancer or other medical conditions, a transplant, or radiation or drug treatment (such as steroids, cancer chemotherapy, or other drugs that affect immune cell function).
- Your thymus has been removed or you have a thymus disorder, such as myasthenia gravis, DiGeorge syndrome, or thymoma.
- Your doctor will help you decide whether you can receive the vaccine.
Adults 60 years of age and older who cannot avoid travel to a yellow fever area should discuss vaccination with their doctor. They might be at increased risk for severe problems following vaccination.
Infants 6 through 8 months of age, pregnant women, and nursing mothers should avoid or postpone travel to an area where there is risk of yellow fever. If travel cannot be avoided, discuss vaccination with your doctor.

If you cannot get the vaccine for medical reasons, but require proof of yellow fever vaccination for travel, your doctor can give you a waiver letter if he considers the risk acceptably low. If you plan to use a waiver, you should also contact the embassy of the countries you plan to visit for more information.

Yellow Fever vaccine side-effects

A vaccine, like any medicine, could cause a serious reaction. But the risk of a vaccine causing serious harm, or death, is extremely low.

Mild problems

Yellow fever vaccine has been associated with fever, and with aches, soreness, redness or swelling where the shot was given.

These problems occur in up to 1 person out of 4. They usually begin soon after the shot, and can last up to a week.

Severe problems

Severe allergic reaction to a vaccine component (about 1 person in 55,000).
Severe nervous system reaction (about 1 person in 125,000).
Life-threatening severe illness with organ failure (about 1 person in 250,000). More than half the people who suffer this side effect die.

These last two problems have never been reported after a booster dose.

References

Thimerosal in Vaccines Questions and Answers. https://www.fda.gov/vaccines-blood-biologics/vaccines/thimerosal-vaccines-questions-and-answers
Thimerosal and Vaccines. https://www.fda.gov/vaccines-blood-biologics/safety-availability-biologics/thimerosal-and-vaccines
IOM (Institute of Medicine). Immunization Safety Review: Vaccines and Autism. Washington, D.C.: National Academy Press: 2004 (Executive Summary, at 7).
Christensen DL, Baio J, Van Naarden Braun K, et al. Prevalence and Characteristics of Autism Spectrum Disorder Among Children Aged 8 Years–Autism and Developmental Disabilities Monitoring Network, 11 Sites, United States, 2012. MMWR Surveill Summ 2016;65:1-23.
Hviid A, Stellfeld M, Wohlfahrt J, Melbye M. Association between thimerosal-containing vaccine and autism. JAMA. 2003;290:1763–6.
Madsen KM, Hviid A, Vestergaard M, Schendel D, Wohlfahrt J, et al. A population-based study of measles, mumps, and rubella vaccination and autism. N Engl J Med. 2002;347 (19):1477–1482.
Price C. et al. (2010) Prenatal and Infant Exposure to Thimerosal from Vaccines and Immunoglobulins and Risk of Autism. Pediatrics. 126: 656-664.
Schechter, R., et al., (2008) Continuing Increases in Autism Reported to California’s Developmental Services System. Arch Gen Psychiatry. 65(1):19-24.
Thompson, WW., et al. (2007) Early thimerosal exposure and neuropsychological outcomes at 7 and 10 years. N. Engl. J. Med 2007. 357:1281-92.
Mercury and health. https://www.who.int/news-room/fact-sheets/detail/mercury-and-health
Chickenpox. https://www.vaccines.gov/diseases/chickenpox/index.html
https://www.fda.gov/downloads/BiologicsBloodVaccines/Vaccines/ApprovedProducts/UCM142813.pdf
https://www.fda.gov/downloads/BiologicsBloodVaccines/Vaccines/ApprovedProducts/UCM123793.pdf
Key Facts About Seasonal Flu Vaccine. https://www.cdc.gov/flu/protect/keyfacts.htm
Haemophilus influenzae Disease (Including Hib). https://www.cdc.gov/hi-disease/about/types-infection.html
Meningococcal Disease. https://www.cdc.gov/meningococcal/about/index.html
https://www.fda.gov/downloads/BiologicsBloodVaccines/Vaccines/ApprovedProducts/UCM142576.pdf
https://wwwnc.cdc.gov/travel