WHO issues interim recommendations for use of Pfizer-BioNTech COVID-19 vaccine (8 January 2021)

Key Messages:

In settings with community transmission, it is recommended that priority be initially given to health workers at high risk, and older people with/without comorbidities.

Protecting high-risk health care workers serves the following purposes:

  1. Protect the individual health workers
  2. Protect critical essential services during the COVID-19 pandemic
  3. Prevent onward transmission to vulnerable people

Protecting older people will have the greatest public health impact in terms of reducing the number of deaths.

Age:

The vaccine is intended for use by persons 16 years-of-age and older.

Administration:

The recommended schedule is two doses (30 mcg, 0.3 ml each) administered intramuscularly into the deltoid muscle.

An interval of 21-28 days between the two doses is recommended. If the second dose is inadvertently administered less than 21 days after the first dose, the dose need not be repeated. If the second dose is inadvertently delayed, it should be administered as soon as possible thereafter (according to manufacturer’s instructions).

It is currently recommended that individuals do not receive more than two doses in total.

Considerations for deferring the second dose:

Some countries have considered delaying administration of the second dose to allow for a higher initial coverage. This is based on the observation that efficacy has been shown to start from the 12th day after the first dose and reached about 89% between days 14 and 21, at the time when the second dose was given. There is no data on longer term efficacy for a single dose of the vaccine. It is important to note that neutralizing antibody responses are modest after the first dose and substantially increase after the second dose.

WHO’s present recommendation is that the interval between doses may be extended up to 42 days (6 weeks), based on currently available clinical trial data. Such adjustments to dose intervals should not affect the likelihood of receiving the second dose.

Booster Doses:

The need for and timing of booster doses will be evaluated as further data accumulate.

Interchangeability with other vaccines:

It is currently recommended that the same product should be used for both doses.

If different COVID-19 vaccine products are inadvertently administered in the two doses, no additional doses of either vaccine are currently recommended.

Co-administration with other vaccines:

There should be a minimum interval of 14 days between administration of this vaccine and any other vaccine against other conditions until more data is available.

Contraindications:

A history of severe allergic reaction (e.g. anaphylaxis) to any component of the vaccine is a contraindication to vaccination.

In particular, this vaccine should not be administered to anyone with a known history of severe allergic reaction to polyethylene glycol (PEG) or related molecules.

Precautions:

A history of any immediate allergic reaction to any other vaccine or injectable therapy (i.e. intramuscular, intravenous, or subcutaneous vaccines or therapies) is considered as a precaution but not a contraindication to vaccination. Such persons should be observed for 30 minutes after vaccination in health care settings where anaphylaxis can be immediately treated.

In general, persons with an immediate allergic reaction to the first dose should not receive additional doses. For the purposes of this guidance, an immediate allergic reaction to a vaccine or medication is defined as any hypersensitivity-related signs or symptoms, such as anaphylaxis, urticaria, angioedema, respiratory distress (e.g. wheezing, stridor), that occur within hours of administration. However, subject to individual risk-benefit assessment, specialist services for immunization may allow BNT162b2 to be provided under close medical supervision if it is the only available option for persons at high risk of severe COVID-19.

As a small number of anaphylactic reactions have also been reported in vaccinees without a history of severe allergic reactions, WHO recommends that BNT162b2 vaccine should be administered only in settings where anaphylaxis can be treated. Until more
data and insights are available with regard to severe allergic reactions to BNT162b2 vaccination, all vaccinees should be observed for at least 15 minutes after vaccination.

Food, contact, or seasonal allergies are not considered a precaution.

The vial stoppers are not made with natural rubber latex, and there is no contraindication or precaution to vaccination for persons with a latex allergy.

In addition, as BNT162b2 does not contain eggs or gelatin, there is no contraindication or precaution to vaccination for persons with allergies to these substances.

Anyone with an acute febrile illness (body temperature over 38.5 ºC) should postpone vaccination until they are afebrile.

Vaccination of specific populations:

I. Populations for which supportive data are available from phase 2/3 clinical trials

Older people:

The efficacy and safety of the vaccine are comparable across all age groups (above the age of 16). Vaccination is recommended for older persons.

Persons with comorbidities:

Vaccination is recommended for persons with comorbidities that have been identified as increasing the risk of severe COVID-19, such as:

  • hypertension
  • diabetes mellitus
  • asthma
  • pulmonary, liver and kidney disease
  • chronic (stable and controlled) infection with HIV, Hepatitis B virus, and Hepatitis C virus

II. Population for which limited or no data exist from phase 2/3 clinical trials

Persons above 85 years of age:

People above 85 years of age and very frail older persons were not included in the clinical trials. However, available data suggests that the benefits of vaccination outweigh the potential risks. Vaccination is recommended for older persons without an upper age limit.

Children and adolescents below the age of 16 years:

There are no data for children or adolescents below the age of 16 years. Until such data are available, persons below 16 years of age should not be vaccinated.

Pregnant women:

WHO recommends not to use BNT162b2 in pregnancy, unless the benefit of vaccinating a pregnant woman outweighs the potential vaccine risks, such as in health workers at high risk of exposure and pregnant women with comorbidities placing them in a high-risk group for severe COVID-19.

WHO does not recommend pregnancy testing prior to vaccination.

Lactating women:

The BNT162b2 vaccine is not a live virus vaccine and the mRNA does not enter the nucleus of the cell and is degraded quickly. Therefore, it is biologically and clinically unlikely to pose a risk to the breastfeeding child. On the basis of these considerations, a lactating woman who is part of a group recommended for vaccination, e.g. health workers, should be offered vaccination on an equivalent basis.

WHO does not recommend discontinuing breastfeeding after vaccination.

Persons living with HIV:

Persons living with HIV may be at higher risk of severe COVID-19. Among the phase 2/3 clinical trial participants with well-controlled HIV, there were no reported differences in safety signals.

HIV-positive persons who are well controlled on highly active antiretroviral therapy and are part of a group recommended for vaccination can be vaccinated.

It is not necessary to test for HIV infection prior to vaccine administration.

Immunocompromised persons:

Immunocompromised persons are at higher risk of severe COVID-19. Available data are currently insufficient to assess vaccine efficacy or vaccine-associated risks in severely immunocompromised persons. It is possible that the immune response to the vaccine
may be reduced, which may alter its effectiveness. In the interim, given that the vaccine is not a live virus, immunocompromised persons who are part of a group recommended for vaccination may be vaccinated.

Persons with autoimmune conditions:

Persons with autoimmune conditions who have no contraindications to
vaccination may be vaccinated.

Persons who have previously had SARS-CoV-2 infection:

Vaccination may be offered regardless of a person’s history of symptomatic or asymptomatic SARS-CoV-2 infection.

Viral or serological testing for prior infection is not recommended for the purpose of decision-making about vaccination. Available data from the phase 2/3 trials indicate that BNT162b2 is safe in people with evidence of prior SARS-CoV-2 infection.

The added protection of vaccinating previously infected individuals is yet to be established. Despite the potential for reinfection, currently available data indicate that symptomatic reinfection within 6 months after an initial infection is rare. Thus, persons with PCR confirmed SARS-CoV-2 infection in the preceding 6 months may delay vaccination until near the end of this period.

Persons with current active COVID-19:

Vaccination of persons with acute symptomatic SARS-CoV-2 should be deferred until they have recovered from acute illness and the criteria for discontinuation of isolation have been met. There are no data to support a recommendation of a minimal interval between onset of symptoms and vaccination.

Persons who previously received passive antibody therapy for COVID-19:

Currently there are no data on the safety or efficacy of vaccination in persons who received monoclonal antibodies or convalescent plasma as part of COVID-19 treatment. Hence, as a precautionary measure, vaccination should be deferred for at least 90 days to avoid interference of the antibody treatment with vaccine-induced immune responses.

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