What to know about coronavirus booster shots in the U.S.

A health-care worker fills a syringe with the Pfizer-BioNTech coronavirus vaccine at the American Museum of Natural History in New York on July 22. (Mary Altaffer/AP)

The Biden administration is rolling out coronavirus vaccine booster shots for certain groups after the Centers for Disease Control and Prevention endorsed a third dose of the Pfizer-BioNTech vaccine for Americans over 65 and adults at heightened risk of severe illness.

The administration had announced plans to make booster shots available to all Americans, citing concerns about people’s immunity from shots waning over time. The decision comes amid a surge in infections from the delta variant across the country, all while vaccinations rates have slowed.

Qualifying Pfizer-BioNTech vaccine recipients can get a booster six months after the date of their second dose. Officials said they will address recommendations for the Moderna and Johnson & Johnson vaccines after reviewing relevant data.

Here’s what you need to know about booster shots and their rollout.

Coronavirus: What you need to know

The latest: The CDC has loosened many of its recommendations for battling the coronavirus, a strategic shift that puts more of the onus on individuals, rather than on schools, businesses and other institutions, to limit viral spread.

Variants: BA.5 is the most recent omicron subvariant, and it’s quickly become the dominant strain in the U.S. Here’s what to know about it, and why vaccines may only offer limited protection.

Vaccines: For people under 50, second booster doses are on hold while the Biden administration works to roll out shots specifically targeting the omicron subvariants this fall. Immunizations for children under 5 became available this summer. Here’s what to know about how vaccine efficacy could be affected by your prior infections and booster history.

Guidance: CDC guidelines have been confusing — if you get covid, here’s how to tell when you’re no longer contagious. We’ve also created a guide to help you decide when to keep wearing face coverings.

Where do things stand? See the latest coronavirus numbers in the U.S. and across the world. The omicron variant is behind much of the recent spread.

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