COVID-19 Vaccine

COVID-19 Vaccine

On December 11, 2020, the U.S. Food and Drug Administration (FDA) issued the first emergency use authorization (EUA) for a coronavirus (COVID-19) vaccine for the prevention of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in individuals 16 years of age and older 1). The emergency use authorization (EUA) allows the Pfizer-BioNTech COVID-19 vaccine to be distributed in the U.S. However, it is your choice to receive or not receive the Pfizer-BioNTech COVID-19 Vaccine. The Moderna COVID-19 Vaccine for the prevention of COVID-19 in individuals 18 years and older is currently undergoing review by the Vaccines and Related Biological Products Advisory Committee.

As with other coronaviruses, COVID-19 also known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an RNA virus which encodes four major structural proteins. Most vaccine candidates focus on immunization with the spike glycoprotein, which is the main target for neutralizing antibodies following infection. Neutralizing antibodies that block viral entry into host cells by preventing interaction between the spike protein and the host cell are expected to be protective.

The Pfizer/BioNTech vaccine is a lipid nanoparticle-formulated messenger RNA (mRNA) vaccine. The mRNA encodes the SARS-CoV-2 full length spike protein. The mRNA in the vaccine is translated and transcribed by your body to produce the spike protein. The protein then acts as an intracellular antigen to stimulate the immune response. The mRNA in the vaccine is normally degraded within a few days and cannot incorporate into the host genome. Data from the Pfizer-BioNTech vaccine trials undertaken in over 40,000 individuals indicate high vaccine efficacy, with no serious safety concerns observed.

The Pfizer-BioNTech COVID-19 vaccine is an unapproved vaccine that may prevent COVID-19. There is no FDA-approved vaccine to prevent COVID-19. Pfizer-BioNTech COVID-19 Vaccine is still being studied in clinical trials. In clinical trials, approximately 20,000 individuals 16 years of age and older have received at least 1 dose of the Pfizer-BioNTech COVID-19 vaccine. In an ongoing clinical trial, the Pfizer-BioNTech COVID-19 vaccine has been shown to prevent COVID-19 following 2 doses given 3 weeks apart. The duration of protection against COVID-19 is currently unknown.

Furthermore, at this time there are no data on the size of the effect of COVID-19 vaccines on transmission. Evidence is expected to accrue during the course of the vaccine programme, and until that time the Vaccines and Related Biological Products Advisory Committee is not in a position to advise vaccination solely on the basis of indirect protection. Once sufficient evidence becomes available the committee will consider options for a cocooning strategy for immunosuppressed individuals, including whether any specific vaccine is preferred in this population.

Pfizer BioNTech COVID-19 Vaccine is administered as a series of two intramuscular shots in your upper arm, three weeks apart. The available safety data to support the  emergency use authorization (EUA) include 37,586 of the participants enrolled in an ongoing randomized, placebo-controlled international study, the majority of whom are U.S. participants. These participants, 18,801 of whom received the vaccine and 18,785 of whom received saline placebo, were followed for a median of two months after receiving the second dose. The most commonly reported side effects, which typically lasted several days, were pain at the injection site, tiredness, headache, muscle pain, chills, joint pain, and fever. Of note, more people experienced these side effects after the second dose than after the first dose, so it is important for vaccination providers and recipients to expect that there may be some side effects after either dose, but even more so after the second dose.

The Pfizer-BioNTech COVID-19 vaccine is being given to:

  • some people aged 80 and over who already have a hospital appointment in the next few weeks
  • people who live or work in care homes
  • health care workers at high risk

The Pfizer-BioNTech COVID-19 vaccine will be offered more widely, and at other locations, as soon as possible.

The order in which people will be offered the vaccine is based on advice from the Vaccines and Related Biological Products Advisory Committee.

Other COVID-19 vaccines in development

AstraZeneca COVID-19 vaccine uses a replication deficient chimpanzee adenovirus as a vector that encodes the full-length SARS-CoV2 spike protein. Chimpanzee adenoviruses are non-enveloped viruses, meaning that the glycoprotein antigen is not present on the surface of the vector, but is only expressed at high levels once the vector enters the target cells. Genes are inserted to render the virus replication incompetent, and to enhance immunogenicity. Once the vector is in the nucleus, mRNA encoding the spike protein is produced that then enters the cytoplasm. This leads to translation of the target protein which acts as an intracellular antigen. Headline data from vaccine trials undertaken indicate high vaccine efficacy, with no serious safety events related to the vaccine. After the Vaccines and Related Biological Products Advisory Committee has been given the opportunity to review Phase 3 data (data on vaccine safety and efficacy) on this vaccine, this statement will be updated.

Currently, there are three main types of COVID-19 vaccines that are or soon will be undergoing large-scale (Phase 3) clinical trials in the United States. Below is a description of how each type of vaccine prompts our bodies to recognize and protect us from the virus that causes COVID-19. None of these vaccines can give you COVID-19.

  1. Messenger RNA (mRNA) vaccines contain material from the virus that causes COVID-19 that gives your cells instructions for how to make a harmless protein that is unique to the virus. After your cells make copies of the protein, they destroy the genetic material from the vaccine. Your body recognizes that the protein should not be there and build T-lymphocytes and B-lymphocytes that will remember how to fight the virus that causes COVID-19 if you are infected in the future.
  2. Protein subunit vaccines include harmless pieces (proteins) of the virus that cause COVID-19 instead of the entire germ. Once vaccinated, your immune system recognizes that the proteins don’t belong in your body and begins making T-lymphocytes and antibodies. If you are ever infected in the future, memory cells will recognize and fight the virus.
  3. Vector vaccines contain a weakened version of a live virus—a different virus than the one that causes COVID-19—that has genetic material from the virus that causes COVID-19 inserted in it (this is called a viral vector). Once the viral vector is inside your cells, the genetic material gives cells instructions to make a protein that is unique to the virus that causes COVID-19. Using these instructions, your cells make copies of the protein. This prompts your bodies to build T-lymphocytes and B-lymphocytes that will remember how to fight that virus if you are infected in the future.

How does COVID-19 vaccine work?

The Pfizer-BioNTech COVID-19 Vaccine contains messenger RNA (mRNA), which is genetic material. The vaccine contains a small piece of the SARS-CoV-2 virus’s mRNA that instructs cells in your body to make the virus’s distinctive “spike” protein. When a person receives this vaccine, their body produces copies of the spike protein, which does not cause disease, but triggers the immune system to learn to react defensively, producing an immune response against SARS-CoV-2.

COVID-19 mRNA vaccines are given in your upper arm muscle. Once the instructions (mRNA) are inside the muscle cells, the cells use them to make the protein piece. After the protein piece is made, the cell breaks down the instructions and gets rid of them.

Next, the cell displays the protein piece on its surface. Your immune systems recognize that the “spike” protein doesn’t belong there and begin building an immune response and making antibodies, like what happens in natural infection against COVID-19.

At the end of the process, your body has learned how to protect against future infection.

To understand how COVID-19 vaccines work, it helps to first look at how your body fights illness. When germs, such as the virus that causes COVID-19, invade your body, they attack and multiply. This invasion, called an infection, is what causes illness. Your immune system uses several tools to fight infection. Blood contains red cells, which carry oxygen to tissues and organs, and white or immune cells, which fight infection. Different types of white blood cells fight infection in different ways:

  • Macrophages are white blood cells that swallow up and digest germs and dead or dying cells. The macrophages leave behind parts of the invading germs called antigens. The body identifies antigens as dangerous and stimulates antibodies to attack them.
  • B-lymphocytes are defensive white blood cells. They produce antibodies that attack the pieces of the virus left behind by the macrophages.
  • T-lymphocytes are another type of defensive white blood cell. They attack cells in the body that have already been infected.

The first time a person is infected with the virus that causes COVID-19, it can take several days or weeks for their body to make and use all the germ-fighting tools needed to get over the infection. After the infection, the person’s immune system remembers what it learned about how to protect the body against that disease.

The body keeps a few T-lymphocytes, called memory cells, that go into action quickly if the body encounters the same virus again. When the familiar antigens are detected, B-lymphocytes produce antibodies to attack them. Experts are still learning how long these memory cells protect a person against the virus that causes COVID-19.

It typically takes a few weeks for the body to produce T-lymphocytes and B-lymphocytes after vaccination. Therefore, it is possible that a person could be infected with the virus that causes COVID-19 just before or just after vaccination and then get sick because the vaccine did not have enough time to provide protection.

Sometimes after vaccination, the process of building immunity can cause symptoms, such as fever. These symptoms are normal and are a sign that the body is building immunity.

How the COVID-19 vaccine is given?

The COVID-19 vaccine is given as an intramuscular (IM) injection into your upper arm. The Pfizer-BioNTech COVID-19 vaccine is given as 2 doses, at least 21 days apart.

There are no data available on the interchangeability of the Pfizer-BioNTech COVID-19 Vaccine with other COVID-19 vaccines to complete the vaccination series. Individuals who have received one dose of Pfizer-BioNTech COVID-19 Vaccine should receive a second dose of Pfizer-BioNTech COVID-19 Vaccine to complete the vaccination series.

Who should not get COVID-19 vaccine?

You should not get the Pfizer-BioNTech COVID-19 Vaccine if you:

  • had a severe allergic reaction after a previous dose of this vaccine
  • had a severe allergic reaction to any ingredient of this vaccine

Can I receive the COVID-19 vaccine with other vaccines?

There is no information on the use of the Pfizer-BioNTech COVID-19 Vaccine with other vaccines.

Can I receive the COVID-19 vaccine if I am pregnant or breastfeeding?

If you are pregnant or breastfeeding, discuss your options with your healthcare provider.

There are no data as yet on the safety of COVID-19 vaccines in pregnancy, either from human or animal studies. Given the lack of evidence, the Vaccines and Related Biological Products Advisory Committee favors a precautionary approach and does not currently advise COVID-19 vaccination in pregnancy.

Women should be advised not to come forward for vaccination if they may be pregnant or are planning a pregnancy within three months of the first dose.

Data are anticipated which will inform discussions on vaccination in pregnancy. The Vaccines and Related Biological Products Advisory Committee will review these as soon as they become available.

You should wait to have the COVID-19 vaccine:

  • if you’re pregnant you should not be vaccinated – you should wait until you’ve had your baby
  • if you’re breastfeeding – you should wait until you’ve stopped breastfeeding
  • If you were breastfeeding when you had the first dose you are advised not to have the second dose until you have finished breastfeeding
  • if you are planning to get pregnant in the next 3 months, you should delay your vaccination
  • if you know you are not pregnant you can start the two-dose course now and you should avoid getting pregnant until at least 2 months after the second dose
  • if you have had the first dose and then become pregnant you should delay the second dose until after the pregnancy is over

If you have the COVID-19 vaccine, you should not get pregnant for at least 2 months after having the 2nd dose.

If you later find out you were pregnant when you had the COVID-19 vaccine, do not worry. The vaccine cannot give you or your baby COVID-19.

There’s no evidence it’s unsafe if you’re pregnant or breastfeeding. But more evidence is needed before you can be offered the vaccine.

This advice is precautionary until additional evidence is available to support the use of this vaccine in pregnancy and breastfeeding.

Will the COVID-19 vaccine give me COVID-19?

No. The Pfizer-BioNTech COVID-19 Vaccine does not contain SARS-CoV-2 and cannot give you COVID-19.

What are the ingredients in the Pfizer-BioNTech COVID-19 Vaccine?

The Pfizer BioNTech COVID-19 Vaccine includes the following ingredients 2): mRNA, lipids 3).

Who is at risk for coronavirus (COVID-19) infections?

Coronavirus (COVID-19) can make anyone seriously ill. But for some people, the risk is higher.

There are 2 levels of higher risk:

  1. People at high risk (clinically extremely vulnerable)
  2. People at moderate risk (clinically vulnerable)

People at high risk (clinically extremely vulnerable)

You may be at high risk from coronavirus (COVID-19) if you:

  • have had an organ transplant
  • are having chemotherapy or antibody treatment for cancer, including immunotherapy
  • are having an intense course of radiotherapy (radical radiotherapy) for lung cancer
  • are having targeted cancer treatments that can affect the immune system (such as protein kinase inhibitors or PARP inhibitors)
  • have blood or bone marrow cancer (such as leukemia, lymphoma or myeloma)
  • have had a bone marrow or stem cell transplant in the past 6 months, or are still taking immunosuppressant medicine
  • have been told by a doctor you have a severe lung condition (such as cystic fibrosis, severe asthma or severe chronic obstructive pulmonary disease [COPD])
  • have a condition that means you have a very high risk of getting infections (such as severe combined immunodeficiency [SCID] or sickle cell)
  • are taking medicine that makes you much more likely to get infections (such as high doses of steroids or immunosuppressant medicine)
  • have a serious heart condition and are pregnant
  • have a problem with your spleen or your spleen has been removed (splenectomy)
  • are an adult with Down’s syndrome
  • are an adult who is having dialysis or has severe (stage 5) long-term kidney disease
  • have been classed as clinically extremely vulnerable, based on clinical judgement and an assessment of your needs

People at moderate risk (clinically vulnerable)

People at moderate risk from coronavirus (COVID-19) include people who:

  • are 70 or older
  • have a lung condition that’s not severe (such as asthma, COPD, emphysema or bronchitis)
  • have heart disease (such as heart failure)
  • have diabetes
  • have chronic kidney disease
  • have liver disease (such as hepatitis)
  • have a condition affecting the brain or nerves (such as Parkinson’s disease, motor neurone disease, multiple sclerosis or cerebral palsy)
  • have a condition that means they have a high risk of getting infections
  • are taking medicine that can affect the immune system (such as low doses of steroids)
  • are very obese (a BMI of 40 or above)
  • are pregnant

If you’re at high risk (clinically extremely vulnerable) from coronavirus (COVID-19), there are things you can do to help keep yourself safe.

DO

  • try to stay at least 2 meters (3 steps) away from anyone you do not live with (or anyone not in your support bubble)
  • wash your hands with soap and water often – do this for at least 20 seconds
  • use hand sanitizer gel if soap and water are not available
  • wash your hands as soon as you get home
  • wear something that covers your nose and mouth in places where it’s hard to stay away from other people, such as on public transport, in shops and in hospitals

Work

  • You should work from home if possible. Your employer should support you to do this.
  • If you cannot work from home and you’re concerned about having to go to work, talk to your employer. Employers should make sure suitable arrangements are in place so you can go to work.

Shopping

To reduce your risk from coronavirus (COVID-19), you may want to:

  • do your shopping online
  • ask family or friends to collect shopping for you
  • avoid busy times if you go shopping.

Who can get the COVID-19 vaccine?

Current evidence strongly indicates that the single greatest risk of mortality from COVID-19 is increasing age and that the risk increases exponentially with age 4). Mathematical modelling indicates that the optimal strategy for minimizing future deaths or quality adjusted life year (QALY) losses is to offer vaccination to older age groups first. These models assume an available vaccine is both safe and effective in older adults 5). Data also indicate that the absolute risk of mortality is higher in those over 65 years than that seen in the majority of younger adults with an underlying health condition (see above). Accordingly, the Vaccines and Related Biological Products Advisory Committee’s advice largely prioritizes based on age.

Age-based programmes are usually easier to implement and therefore achieve higher vaccine uptake. An age-based programme is also likely to increase uptake in those with clinical risk factors as the prevalence of these increases with age.

The Vaccines and Related Biological Products Advisory Committee’s advice is to offer vaccination to those aged 65 years and over followed by those in clinical risk groups aged 16 years and over.

The risk groups identified by the committee are set out below:

  • chronic respiratory disease, including chronic obstructive pulmonary disease (COPD), cystic fibrosis and severe asthma
  • chronic heart disease (and vascular disease)
  • chronic kidney disease
  • chronic liver disease
  • chronic neurological disease including epilepsy
  • Down’s syndrome
  • severe and profound learning disability
  • diabetes
  • solid organ, bone marrow and stem cell transplant recipients
  • people with specific cancers
  • immunosuppression due to disease or treatment
  • asplenia and splenic dysfunction
  • morbid obesity
  • severe mental illness

Many individuals who are clinically extremely vulnerable will have some degree of immunosuppression or be immunocompromised and may not respond as well to the vaccine. Therefore, those who are clinically extremely vulnerable should continue to follow government advice on reducing their risk of infection. Consideration has been given to vaccination of household contacts of immunosuppressed individuals.

Older adults resident in care homes

There is clear evidence that those living in residential care homes for older adults have been disproportionately affected by COVID-19 6) as they have had a high risk of exposure to infection and are at higher clinical risk of severe disease and mortality. Given the increased risk of outbreaks, morbidity and mortality in these closed settings, these adults are considered to be at very high risk. The committee’s advice is that this group should be the highest priority for vaccination. Vaccination of residents and staff at the same time is considered to be a highly efficient strategy within a mass vaccination programme with the greatest potential impact.

The order of priority for each group in the population corresponds with data on the number of individuals who would need to be vaccinated to prevent one death, estimated from UK data obtained from March to June 2020 7).

This priority list is as follows:

  1. residents in a care home for older adults and their carers
  2. all those 80 years of age and over and frontline health and social care workers
  3. all those 75 years of age and over
  4. all those 70 years of age and over and clinically extremely vulnerable individuals
  5. all those 65 years of age and over
  6. all individuals aged 16 years to 64 years with underlying health conditions which put them at higher risk of serious disease and mortality
  7. all those 60 years of age and over
  8. all those 55 years of age and over
  9. all those 50 years of age and over

It is estimated that taken together, these groups represent around 99% of preventable mortality from COVID-19.

The vaccine advisory committee advises that implementation of the COVID-19 vaccine programme should aim to achieve high vaccine uptake. An age-based programme will likely result in faster delivery and better uptake in those at the highest risk.

Health and social care workers

Frontline health and social care workers are at increased personal risk of exposure to infection with COVID-19 and of transmitting that infection to susceptible and vulnerable patients in health and social care settings. The committee considers frontline health and social care workers who provide care to vulnerable people a high priority for vaccination. Protecting them protects the health and social care service and recognizes the risks that they face in this service. Even a small reduction in transmission arising from vaccination would add to the benefits of vaccinating this population, by reducing transmission from health and social care workers to multiple vulnerable patients and other staff members. This group includes those working in hospice care and those working temporarily in the COVID-19 vaccination programme who provide face-to-face clinical care.

There is evidence that infection rates are higher in residential care home staff 8), than in those providing domiciliary care or in healthcare workers. Care home workers are therefore considered a very high priority for vaccination.

Prioritization amongst health and social care workers

Frontline health and social care workers at high risk of acquiring infection, at high individual risk of developing serious disease, or at risk of transmitting infection to multiple vulnerable persons or other staff in a healthcare environment, are considered of higher priority for vaccination than those at lower risk. This prioritization should be taken into account during vaccine deployment.

Pregnancy and COVID-19

There’s no evidence that pregnant women are more likely to get seriously ill from coronavirus (COVID-19). But pregnant women have been included in the list of people at moderate risk (clinically vulnerable) as a precaution. This is because pregnant women can sometimes be more at risk from viruses like flu. It’s not clear if this happens with COVID-19. But because it’s a new virus, it’s safer to include pregnant women in the moderate-risk group.

It may be possible for you to pass COVID-19 to your baby before they are born. But when this has happened, the babies have got better.

There’s no evidence COVID-19 causes miscarriage or affects how your baby develops in pregnancy.

When to seek medical help

Call your doctor (obstetrician) or maternity team immediately if:

  • your baby is moving less than usual
  • you cannot feel your baby moving
  • there is a change to your baby’s usual pattern of movements
  • you have any bleeding from your vagina
  • you’re feeling very anxious or worried
  • you have a headache that does not go away
  • you get shortness of breath when resting or lying down

Do not wait until the next day – call immediately, even if it’s the middle of the night.

COVID-19 vaccine advice if you’re of childbearing age, pregnant or breastfeeding

You should wait to have the COVID-19 vaccine:

  • if you’re pregnant you should not be vaccinated – you should wait until you’ve had your baby
  • if you’re breastfeeding – you should wait until you’ve stopped breastfeeding
  • If you were breastfeeding when you had the first dose you are advised not to have the second dose until you have finished breastfeeding
  • if you are planning to get pregnant in the next 3 months, you should delay your vaccination
  • if you know you are not pregnant you can start the two-dose course now and you should avoid getting pregnant until at least 2 months after the second dose
  • if you have had the first dose and then become pregnant you should delay the second dose until after the pregnancy is over

If you have the COVID-19 vaccine, you should not get pregnant for at least 2 months after having the 2nd dose.

If you later find out you were pregnant when you had the COVID-19 vaccine, do not worry. The vaccine cannot give you or your baby COVID-19.

There’s no evidence it’s unsafe if you’re pregnant or breastfeeding. But more evidence is needed before you can be offered the vaccine.

This advice is precautionary until additional evidence is available to support the use of this vaccine in pregnancy and breastfeeding.

What to do if you’re pregnant

If you’re pregnant, it’s important you:

  • wash your hands regularly
  • stay at home as much as possible and follow the advice on social distancing, such as staying at least 2 meters (3 steps) away from other people
  • stay away from anyone who has symptoms of COVID-19

You still need to go to all of your pregnancy (antenatal) scans and appointments unless you’re told not to.

You may find that:

  • some midwife appointments are online, by phone or by video call
  • you may be asked to wear a mask or gown when you’re in a hospital or clinic
  • some appointments may be cancelled or rescheduled – if an appointment is cancelled, it will be rescheduled, or you’ll be able to rebook it

This is to help keep everyone safe and stop the spread of COVID-19.

If you’re unsure if you can bring your partner to your appointment, ask your midwife or maternity team.

What are the risks of the Pfizer-BioNTech COVID-19 vaccine?

Side effects that have been reported with the Pfizer-BioNTech COVID-19 vaccine include 9):

  • injection site pain
  • tiredness
  • headache
  • muscle pain
  • chills
  • joint pain
  • fever
  • injection site swelling
  • injection site redness
  • nausea
  • feeling unwell
  • swollen lymph nodes (lymphadenopathy)

There is a remote chance that the Pfizer-BioNTech COVID-19 vaccine could cause a severe allergic reaction. A severe allergic reaction would usually occur within a few minutes to one hour after getting a dose of the Pfizer-BioNTech COVID-19 Vaccine. Signs of a severe allergic reaction can include 10):

  • Difficulty breathing
  • Swelling of your face and throat
  • A fast heartbeat
  • A bad rash all over your body
  • Dizziness and weakness

If you experience a severe allergic reaction, call your local emergency services number or go to the nearest hospital.

These may not be all the possible side effects of the Pfizer-BioNTech COVID-19 Vaccine. Serious and unexpected side effects may occur. Pfizer-BioNTech COVID-19 Vaccine is still being studied in clinical trials.

COVID-19 vaccine side effects

The most commonly reported Pfizer-BioNTech COVID-19 vaccine side effects, which typically lasted several days, were pain at the injection site, tiredness, headache, muscle pain, chills, joint pain, and fever 11). Of note, more people experienced these side effects after the second dose than after the first dose, so it is important for vaccination providers and recipients to expect that there may be some side effects after either dose, but even more so after the second dose

Call the vaccination provider or your healthcare provider if you have any side effects that bother you or do not go away.

Report vaccine side effects to FDA or the CDC Vaccine Adverse Event Reporting System (VAERS). The VAERS toll-free number is 1-800-822-7967 or report online to https://vaers.hhs.gov/reportevent.html. Please include “Pfizer-BioNTech COVID-19 Vaccine EUA” in the first line of box #18 of the report form.

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