The WHO Strategic Advisory Group of Experts on Immunization (SAGE) has issued interim recommendations for the use of the Pfizer BioNTech (BNT162b2) vaccine against COVID-19. This article provides a summary of those interim recommendations; you may access the full guidance document here.

Here is what you need to know.

According to SAGE, the Pfizer-BioNTech COVID-19 mRNA vaccine is safe and effective.

Who can take the vaccine?

The vaccine is safe and effective for all individuals aged 6 months and above. In line with the WHO Prioritization Roadmap and the WHO Values Framework, older adults, immunocompromised persons and health workers are the highest priority-use groups. All efforts should be taken to achieve high vaccine coverage rates in the highest and high priority-use groups. 

Should pregnant and breastfeeding women be vaccinated?

Given the adverse consequences of COVID-19 disease during pregnancy and the increasing data supporting a favorable safety profile of BNT162b2 in pregnancy, WHO recommends the use of BNT162b2 in pregnant individuals. WHO does not recommend pregnancy testing prior to vaccination. WHO does not recommend delaying pregnancy or terminating pregnancy because of vaccination.

Vaccine effectiveness is expected to be similar in breastfeeding women as in other adults. WHO recommends the use of the vaccine in breastfeeding women as in other adults. WHO does not recommend discontinuing breastfeeding because of vaccination. Vaccine-elicited antibodies have been found in breast milk following vaccination of breastfeeding women, suggesting possible neonatal as well as maternal protection.

Who should not take the vaccine?

People with a history of severe allergic reaction to any component of the vaccine should not take it.

Anyone with fever (body temperature over 38.5 ºC) should postpone vaccination until they are afebrile.

Is this vaccine recommended for children and adolescents?

This vaccine is authorized for use for those aged 6 months and older, with an adjustment in the recommended dosage for those aged 6 months to 4 years, and an adjustment for those aged 5-11 years. 

WHO recommends that countries should consider using the vaccine in children aged 6 months and older to 17 only when high vaccine coverage with 2 doses has been achieved in the highest and high priority-use groups as identified in the WHO Prioritization Roadmap. 

Children and adolescents aged 6 months – 17 years of age with comorbidities that put them at significantly higher risk of serious COVID-19 disease, should be offered vaccination, alongside other high-risk groups. 

In accordance with the WHO Prioritization Roadmap, the priority remains to prevent deaths by achieving high vaccine coverage (primary series and boosters) in the highest and high priority-use groups.

In general, children are at lower risk of COVID-19. That is why WHO recommend that countries prioritize vaccinating people who have higher risk first, like people who are older, have existing health conditions and health workers.    

Is it safe?

The Global Advisory Committee on Vaccine Safety (GACVS), a group of experts that provides independent and authoritative guidance to WHO on the topic of safe vaccine use, receives and assesses reports of suspected safety events of potentially international impact. In October 2021, the GACVS COVID-19 subcommittee concluded that the mRNA COVID-19 vaccines have clear benefits in all age groups in reducing hospitalizations and deaths due to COVID-19.

A very rare serious adverse event is myocarditis, which is mainly observed in young males aged 18-35 after the second dose.  These myocarditis cases typically occurred within a few days after vaccination, are generally mild, respond to conservative treatment, and are less severe with better outcomes than classical myocarditis or COVID-19 related myocarditis.

How efficacious is the vaccine?

The Pfizer BioNTech vaccine against COVID-19 has very high efficacy against severe disease and moderate efficacy against symptomatic SARS-CoV-2 infection.

What is the recommended dosage?

For all persons aged 12 years and above, SAGE recommends two doses (30 µg, 0.3 ml each), 4-8 weeks apart given intramuscularly into the deltoid muscle.

For children aged 5 to 11 years SAGE recommends two doses (10 µg, 0.2 ml each) given intramuscularly into the deltoid muscle and provided 4-8 weeks apart, preferentially 8 weeks.

For infants and children aged 6 months to 4 years, the recommended schedule is three doses (3µg, 0.2 ml each): a schedule of two doses 3 weeks apart followed by a third dose at least 8 weeks after the second dose are recommended according to the label. However, countries could consider extending the interval between the first and second dose up to 8 weeks. 

Compliance with the full schedule is recommended and the same product can be used for both doses.

SAGE recommends that severe and moderately immunocompromised persons, including children, should be offered an additional dose of vaccine, as part of the primary series. This is due to the fact that this group is less likely to respond adequately to vaccination following a standard primary vaccination series and are at higher risk of severe COVID-19 disease. 

Is a booster dose recommended for this vaccine? 

The first booster dose is recommended for the highest priority-use groups (e.g. older adults, persons with moderate to severe immunocompromising conditions, and health workers) followed by lower priority-use groups, 4-6 months after the completion of the primary series. If more than 6 months have elapsed since completion of the primary series, the booster dose should be given at the earliest opportunity.

WHO recommends countries should consider a second booster dose 4-6 months after the first booster dose for the highest priority-use groups.

There is currently no recommendation for either first or second booster doses in children under the age of 12, except for children with immunocompromising conditions.

Can this vaccine be ‘mixed and matched’ with other vaccines?

SAGE accepts two doses from different COVID-19 vaccine platforms of WHO Emergency Use Listing (EUL) COVID-19 vaccines as a complete primary series.

For countries considering mix-and match schedules, WHO has made recommendations to ensure equivalent or favourable immunogenicity or vaccine effectiveness for heterologous versus homologous schedules:

  • Either of the WHO EUL COVID-19 vectored vaccines (Janssen or AstraZeneca Vaxzervia/COVISHIELD) can be used as a second dose following a first dose of the Pfizer vaccine, dependent on product availability.
  • The Pfizer vaccine can also be used as a second dose following any of the WHO EUL COVID-19 inactivated vaccines (Sinopharm, Sinovac or Bharat) or any of the vectored vaccines (Janssen or AstraZeneca Vaxzervia/COVISHIELD).
  • The Pfizer vaccines can also be used as a booster dose following any of the COVID-19 vaccines with WHO EUL.

Does it prevent infection and transmission?

There is modest vaccine impact on transmission.

In the meantime, we must maintain and strengthen public health measures that work: masking, physical distancing, handwashing, respiratory and cough hygiene, avoiding crowds, and ensuring good ventilation.

Does it work against new variants?

The vaccine remains effective against virus variants, though for the Omicron variant, vaccine effectiveness against severe and mild disease after two doses is lower compared to Delta, and waning is more rapid. Therefore, a third dose (first booster) is recommended for all adults, and a second booster for the highest priority-use groups.

How does this vaccine compare to other COVID-19 vaccines in use?

It is impossible to compare vaccines head-to-head due to the different approaches taken in designing the respective studies, but overall, all of the vaccines that have achieved WHO Emergency Use Listing are highly effective in preventing severe disease and hospitalization due to COVID-19.