, clearing the way for millions of teenagers to get a third dose of vaccine starting 6 months after their second dose.
The FDA said it was basing its emergency authorization of boosters for 16- and 17-year-olds on data from 200 individuals who were 18-55 years of age when they received a booster dose. They are requiring Pfizer to collect data on safety in postauthorization studies.
“The FDA has determined that the benefits of a single booster dose of the Pfizer-BioNTech COVID-19 Vaccine or Comirnaty outweigh the risks of myocarditis and pericarditis in individuals 16 and 17 years of age to provide continued protection against COVID-19 and the associated serious consequences that can occur including hospitalization and death,” the agency said in a news release.
Israel has been giving booster doses of Pfizer’s vaccine to everyone 12 and up since late August. Data from that country show that myocarditis cases continue to be very rare, even in younger age groups, and are mild and temporary.
The authorization comes as the effectiveness of the current vaccines against the new Omicron variant has become a point of intense scientific inquiry.
Early studies suggest that booster doses may be necessary to keep Omicron at bay, at least until new variant-specific vaccines are ready next spring.
Current evidence suggests that the protection of the vaccines is holding up well against severe disease and death, at least with Delta and early iterations of the virus.
How well they will do against Omicron, and how severe Omicron infections may be for different age groups, remain open questions.
On Dec. 8, the World Health Organization urged countries not to wait for all the science to come in, but to act now to contain any potential threat.
The first pieces of evidence on Omicron suggest that it is highly contagious, perhaps even more than Delta, though early reports suggest symptoms caused by this version of the new coronavirus may be less severe than in previous waves. Experts have cautioned that the true severity of Omicron infections isn’t yet known, since the first cases have been detected in younger people, who tend to have milder COVID-19 symptoms than those of adults and seniors.
“Vaccination and getting a booster when eligible, along with other preventive measures like masking and avoiding large crowds and poorly ventilated spaces, remain our most effective methods for fighting COVID-19,” Acting FDA Commissioner Janet Woodcock, MD, said in a news release. “As people gather indoors with family and friends for the holidays, we can’t let up on all the preventive public health measures that we have been taking during the pandemic. With both the Delta and Omicron variants continuing to spread, vaccination remains the best protection against COVID-19.”
In mid-November, the FDA authorized boosters of the Pfizer vaccine for all individuals 18 and older, but the agency held off on expanding the use of boosters for younger age groups, partly because they have the highest risk of myocarditis, a very rare side effect.
Myocarditis cases seem to be temporary, with patients making a full recovery, though they need to be monitored in the hospital. The risk of myocarditis with a COVID-19 infection is many times higher than it is from a vaccine.
There have been little data to support the need for boosters in this age group, because children and teens tend to experience milder COVID-19 disease, though they are still at risk for post–COVID-19 complications such as long COVID and a delayed reaction to the virus called Post Acute Sequelae of SARS-CoV2 Infection among Children, or PAS-C.
All that changed with the arrival of Omicron.
A version of this article first appeared on WebMD.com.