The Food and Drug Administration could authorize a second Covid-19 vaccine booster early next week, according to two people with knowledge of the plan.
The move comes amid early signs that the U.S. could soon experience another Covid wave as the omicron subvariant, known as BA.2, spreads throughout Europe and other parts of the world. Other countries, including the U.K., Chile, Israel and Sweden, already allow for a fourth vaccine for certain vulnerable populations.
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Earlier this month, Moderna asked the FDA to authorize a fourth Covid shot for all adults, following Pfizer-BioNTech's request for a second booster for people 65 and older. Both companies said protection from the initial booster weakened after a few months.
Experts are still divided on whether an additional dose of the vaccine is necessary for everyone, but many agree a fourth dose may eventually be needed for certain groups, such as older adults.
As of a few days ago, FDA officials had settled on giving Americans age 65 and older the option of getting a second booster of either the Pfizer or the Moderna vaccine. However, in recent days, as officials began seeing small increases in cases in parts of the Northeast, officials considered expanding eligibility to even more Americans, the sources said.
The New York Times, which first reported the news, said late Friday that the Biden administration planned to offer second boosters to Americans age 50 and older.
The FDA did not immediately respond to NBC News' request for comment.
The FDA and the Centers for Disease Control and Prevention are not expected to seek the advice of their advisory committees, known as the Vaccines and Related Biological Products Advisory Committee and the Advisory Committee on Immunization Practices, one of the sources said.
Once the FDA authorizes the fourth shot, the CDC is expected to weigh in.
The FDA has scheduled a vaccine advisory meeting for April 6, but the meeting will not hold a vote and is expected to focus on potential criteria for authorizing a variant-specific Covid vaccine, one person said.
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