The Centers for Disease Control and Prevention on Thursday signed off on booster shots of the Pfizer-BioNTech Covid-19 vaccine for 16- and 17-year-olds for emergency use.
The final approval, from CDC Director Dr. Rochelle Walensky, came hours after the Food and Drug Administration authorized third shots for the age group.
The move opens up additional shots to more Americans amid growing alarm over the omicron variant and the continued spread of the delta variant. Booster shots from Pfizer, Moderna and Johnson & Johnson are already authorized for all adults.
Walensky said in a statement that initial data suggest that a third shot will help strengthen protection against omicron and other variants.
"We know that COVID-19 vaccines are safe and effective," she said, urging older teens to get the booster.
Acting FDA Commissioner Dr. Janet Woodcock said boosters, along with other preventative measures, remain the nation's most effective method for fighting Covid.
"With both the delta and omicron variants continuing to spread, vaccination remains the best protection against COVID-19," she said in a statement.
The Pfizer booster will be available to 16- and 17-year-olds at least six months after they received their second dose of the Pfizer vaccine. Because Pfizer's vaccine and booster shots are the only ones that have been cleared for use in children under 18, "mixing and matching" vaccines and boosters is not an option for this age group. The Moderna and Johnson & Johnson vaccines are authorized for adults 18 and up.
Children under age 18 made up about 22.4 percent of all reported Covid cases nationwide in the week ending Dec. 2, according to American Academy of Pediatrics. They make up about 22.2 percent of the total U.S. population.
Even though children are less likely than adults to suffer from severe outcomes from Covid, a small portion of them do, public health officials and health experts say. More than 5,900 kids have experienced MIS-C, or multisystem inflammatory syndrome in children, a rare but serious Covid-related complication, according to the CDC. Fifty-two children have died from it, according to the agency.
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Dr. Sean O’Leary, vice chair of the infectious diseases committee of the American Academy of Pediatrics, supported the decision to expand boosters to 16- and 17-year-olds, especially as evidence of waning immunity grows and the omicron variant gains a foothold in the U.S.
"In the overall population, boosters really are appearing like it's the way to go because of waning immunity and broader protection with that third dose," he said. "And, in fact, a lot of people are now arguing we shouldn't even think of it as a booster, that we should think of it as part of a three-dose series."
Dr. Walid Gellad, a professor of medicine at the University of Pittsburgh, said that although teens should have the "option" to get a booster, he doesn't think most of them need it.
Kids, especially vaccinated ones, generally don’t get severe disease, he said.
"There are some high-risk kids who got the vaccine a long time ago who may be at very high risk for severe disease" and may need the third shot, he said.
However, he added there's still very limited data on the risks, like myocarditis, a rare inflammatory heart condition, and the benefits of boosting the entire age group. Myocarditis has been most commonly reported in young men after their second dose.
The FDA said on Thursday that benefits of a booster for 16- and 17-year-olds outweighed the risks of myocarditis.
"It's a rare complication," Dr. George Rutherford, a professor of epidemiology at the University of California, San Francisco. "And I can tell you that the risk of myocarditis from the naturally acquired infection is astronomically higher than from the vaccine."
In fact, he said the agency should authorize third shots for an even broader group, down to adolescents as young as 12.
Kids as young as 5 are eligible to receive the initial two doses of Pfizer’s and BioNTech’s vaccine.
The companies asked the FDA to expand emergency use authorization of their booster for older teens on Nov. 30, according to Pfizer CEO Albert Bourla.
The authorization comes as some health experts discuss whether it is appropriate to use the existing vaccines as boosters, and if it would be better instead to wait for an omicron-specific vaccine.
Early data from laboratory studies show the initial two-dose series of the Pfizer-BioNTech vaccine appears to be less effective against omicron, but the companies said Wednesday a booster shot appears to provide strong protection against the new variant.
Dr. Anthony Fauci, the White House's chief medical adviser, told “Andrea Mitchell Reports” on MSNBC on Wednesday that there's “no doubt” among federal health officials that a booster provides "optimal protection" against the virus and its variants.