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CDC endorses Pfizer and Moderna boosters for all adults

The advisory committee's vote in favor of boosters came just hours after the FDA authorized the shots. CDC Director Dr. Rochelle Walensky signed off shortly after.
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An advisory panel to the Centers for Disease Control and Prevention voted on Friday to recommend Pfizer-BioNTech and Moderna’s Covid-19 booster shots to all adults, a move that simplifies who is eligible for an additional dose.

And by evening, CDC Director Dr. Rochelle Walensky had signed off on the recommendation.

Friday’s unanimous vote by the Advisory Committee on Immunization Practices strips away the complicated and confusing criteria that had surrounded boosters, with eligibility limited to certain groups and, initially, certain vaccines. 

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Dr. Sara Oliver, an epidemic intelligence service officer at the CDC, acknowledged that confusion, citing a recent survey that found that 4 in 10 fully vaccinated adults were uncertain if they were eligible for a booster.

Dr. Nirav Shah, president of the Association of State and Territorial Health Officials, underscored the confusion seen by state health officials.

"Not a single state voiced opposition" to expanding eligibility, Shah said.

Committee member Dr. Oliver Brooks, the chief medical officer at Watts HealthCare Corporation in Los Angeles, echoed the need to simplify the eligibility.

"To me, there's no safety reason not to do it," Brooks added.

In a presentation to the committee, Oliver said that the CDC had concluded that Pfizer's booster was safe and effective. While Moderna didn't provide efficacy data, the drugmaker demonstrated that a booster raised antibody levels. For both vaccines, she said, the evidence to date about a heart condition called myocarditis is reassuring.

While it’s unknown whether boosters can stop transmission, Oliver noted that even a reduction in transmission may be important, especially as winter and the holidays approach.

The recommendation makes all adults eligible for a booster shot six months after vaccination with a two-dose mRNA vaccine (from Pfizer or Moderna) or two months after vaccination with the single-dose Johnson & Johnson vaccine. 

Because people can “mix and match” their boosters, the recommendation means that a person can receive any of the three boosters, as long as enough time has passed since their initial vaccination. 

The committee also voted to recommend that people 50 and up should get the booster, while people ages 18 to 50 may choose to do so, based on how they view their individual risk. Adults under 50 in long-term care facilities should also get the booster.

The panel’s vote came as states and cities have decided to go ahead with booster shots prior to signoff from the CDC and Food and Drug Administration. The FDA authorized both companies' boosters for all adults Friday morning, but as early as last week, some states and cities were already offering the doses on their own.

The Biden administration announced plans in August to make boosters available to all adults starting in late September. The FDA rejected Pfizer’s initial request to do so, however, instead opting to limit boosters to older adults and people at high risk of Covid, either due to underlying medical conditions or their occupations. 

Friday's advisory committee included presentations from both Pfizer and Moderna on their booster shots.

Pfizer presented results from its clinical trial on approximately 10,000 people who received either a booster shot or a placebo. Everyone in the trial had received the initial two-dose vaccination series at least six months earlier. The trial found that the booster was 95 percent effective against Covid, and the effects of the booster could be seen less than one week after receiving the shot. 

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Moderna presented much more limited data, consisting of results that were presented during a previous CDC advisory committee meeting. Those results showed the booster raised antibody levels. The company noted, however, that it is monitoring more than 15,000 people who have received a Moderna booster, and results from that group were being compiled.

Both Pfizer and Moderna said that side effects of the booster doses were largely similar to those seen after the initial shots, including arm pain, fatigue and muscle aches. One side effect that both drugmakers found was more common after the booster shot than the initial vaccination was swollen lymph nodes.

While there were no cases of myocarditis, a type of heart inflammation, in either Pfizer or Moderna’s booster trial, Dr. Tom Shimabakuro of the CDC said that the agency had confirmed 12 cases out of 25.9 million people who had received either a Pfizer or Moderna booster. An additional 38 cases are being investigated.

Shimabakuro cautioned that it's still too soon to draw any conclusions after myocarditis risk after the booster, because most of the people who have received a booster dose are older. The risk of myocarditis, though ultimately rare, is higher in men under 30.

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