CDC early Friday issued its first recommendations for who should receive booster doses of the Pfizer-BioNTech Covid-19 vaccine—and, in a departure from an advisory committee's guidance, CDC Director Rochelle Walensky opted to recommend boosters for those at risk of coronavirus exposure due to their jobs.

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ACIP's recommendations

CDC's Advisory Committee on Immunization Practices (ACIP) voted Thursday to recommend booster shots of the Pfizer-BioNTech vaccine six months after a second shot to people ages 65 and older, residents of nursing homes, and those ages 50 to 64 who have underlying medical conditions.

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The panel added that those ages 18 to 49 with underlying medical conditions could determine their own risk and get a booster shot if they wanted one.

Members of the committee argued that booster shots for the general population were unnecessary, as data shows the vaccines remain strong at protecting against severe Covid-19, hospitalization, and death.

"We may move the needle a little bit by giving a booster dose to people," Helen Keipp Talbot, an ACIP member and internist and infectious disease specialist at Vanderbilt University, said. But "the hospitals are full because people are not vaccinated," she added.

The panel also voted 9-6 not to recommend booster shots for people who are at risk of Covid-19 because of their occupation, such as health care workers and teachers—a population for whom FDA had authorized booster doses on Wednesday.

Sarah Long, an ACIP member and professor of pediatrics at Drexel University College of Medicine, said recommending booster shots for people based on occupation is "a very slippery slope" that seemed "uncharacteristically open-ended" given the paucity of data supporting either the necessity or benefit.

However, Talbot argued the recommendation would help boost the health of frontline health care workers and keep hospitals from losing staff. "Having the option to give health care workers a third dose helps us to maintain our staffing," she said.

CDC director overrules ACIP

CDC is not bound by ACIP's recommendations, however, and Walensky ultimately decided to issue a broader recommendation that includes booster shots for those ages 18 to 64 who are at risk of exposure from their occupation or institutional setting.

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The final CDC recommendation aligns with FDA's authorization for booster shots.

In a statement, Walensky said it was her job "to recognize where our actions can have the greatest impact."

"I believe we can best serve the nation's public health needs by providing booster doses for the elderly, those in long-term care facilities, people with underlying medical conditions, and for adults at high risk of disease from occupational and institutional exposures to Covid-19," she said.

Yvonne Maldonado, an infectious disease expert at Stanford University and liaison for the American Academy of Pediatrics to ACIP, said she was "surprised" that Walensky overruled one of ACIP's recommendations, but said she agreed with the decision, saying it "addresses not only waning immunity but those at high risk of exposure."

Walensky added that, while ACIP only reviewed data on the Pfizer-BioNTech vaccine, CDC "will address, with the same sense of urgency, recommendations for the Moderna and [Johnson & Johnson] vaccines as soon as [that] data [is] available."

Biden urges Americans to get booster shots

In a speech Friday, President Joe Biden urged Americans to get a booster shot as soon as they're eligible.

"My message today is this: If you've got the Pfizer vaccine, you got the Pfizer vaccine January, February, March of this year, and you're over 65 years of age, go get the booster," he said. "Or if [you] have a medical condition like diabetes, or you're a frontline worker like a health care worker or a teacher, you can get a free booster."

To the Americans who received vaccines from Moderna or Johnson & Johnson, Biden said they "still have a high degree of protection," but should have the opportunity to get a booster shot later.

Biden also noted that he will be receiving a booster shot, but said he's unsure when that will happen.

Biden added that Americans who remain unvaccinated are not only putting their health at risk but are damaging the economy.

"The vast majority of Americans are doing the right thing," Biden said. "Three quarters of the eligible have gotten at least one shot, but one quarter has not gotten any. In a country as large as ours, that 25% minority can cause an awful lot of damage, and they are causing a lot of damage." (Mandavilli/Mueller, New York Times, 9/23 [1]; Sun/McGinley, Washington Post, 9/24; Mandavilli/Mueller, New York Times, 9/24 [1]; Mandavilli/Mueller, New York Times, 9/24 [2]; Saric, Axios, 9/23; Owens, Axios, 9/24; Branswell, STAT News, 9/23; Levin, New York Times, 9/23; Shear, New York Times, 9/24; Jeong et. al., Washington Post, 9/24)