FDA Approves a Second COVID Booster Shot for Americans Over 50

The Food and Drug Administration approved a second booster dose of a COVID-19 vaccine for Americans over 50 on Tuesday morning, for an extra layer of protection against infection.

Adults over 50 will soon be eligible to get a fourth dose of either Pfizer or Moderna's COVID-19 vaccine if it has been four or more months since their third. The Biden administration had urged the FDA to make this recommendation with research showing that the vaccine's protection against infection starts to wane after three months, and as the omicron subvariant BA.2 spreads in the U.S.

The shots will be available as soon as the Centers for Disease Control signs off on the decision. The federal health agency is expected to say that vaccines are available for anyone interested in getting a second booster without explicitly recommending it, according to the Washington Post.

Currently, fourth doses are only recommended for those with preexisting conditions that put them at a high risk of severe COVID-19 illness.

The question of whether to recommend a fourth dose has been debated. Two large studies out of Israel, where those 60 years or older and medical personnel started getting fourth doses in December, showed that "an additional mRNA booster increases immunogenicity and lowers rates of confirmed infections and severe illness," Pfizer said earlier this month in a request to the FDA to approve a fourth dose.

One of those studies analyzed 1.1 million adults aged 60 and older and showed that people who received a fourth dose were half as likely to get infected and four times less likely to become severely sick than those who had three doses. The other study, of 700 health care workers aged 18 and up, found that those who had a fourth dose had a ten-fold increase in antibodies two weeks after they received the shot, including against omicron.

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But there is concern that by approving a fourth dose it will make people doubt the effectiveness of the COVID-19 vaccines, which are still proving to be highly protective against severe illness, hospitalization and death, even months after a third dose.

Additionally, interest in a first booster dose was low, and of the 65.4% of Americans who are fully vaccinated, only 44% received a booster dose. The White House has also said in recent weeks that they are out of funding to provide a fourth dose to all Americans after Congress failed to agree on funding for their COVID programming.

But amid concern about BA.2 spreading in the U.S. as the country has lifted mask mandates and other pandemic restrictions, along with worries about a new variant popping up, major health agencies met last Wednesday and agreed that offering a second booster to people over 50 was the right choice, the Post reported.

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