US experts are expected to recommend COVID-19 vaccine boosters for all Americans eight months after they received their second dose of the shot, to ensure lasting protection against the coronavirus as the Delta variant spreads across the country.
Federal health officials have been actively looking at whether extra shots for the vaccinated would be needed as early as this autumn, reviewing case numbers in the US as well as the situation in other countries such as Israel, where preliminary studies suggest the vaccine's protection against serious illness dropped among those vaccinated in January.
An announcement on the US booster recommendation is expected as soon as this week, according to two people familiar with the matter who spoke on condition of anonymity.
Doses would only begin to be administered widely once the Food and Drug Administration formally approves the vaccines. That action is expected for the Pfizer shot in the coming weeks.
Last week, US health officials recommended boosters for some with weakened immune systems.
Among the first to receive boosters could be healthcare workers, nursing home residents and other older Americans, who were some of the first Americans to be vaccinated once the shots received emergency use authorisation last December.
Since then, more than 198 million Americans have received at least one dose of a COVID-19 vaccine according to the Centers for Disease Control and Prevention, with more than 168 million fully vaccinated.
Still, the country is experiencing a fourth surge of virus cases due to the more transmissible Delta variant, which is spreading through unvaccinated communities but is also responsible for an increasing number of so-called "breakthrough infections" of fully vaccinated people.
Israel, which exclusively administered the Pfizer shot, has been offering a booster to people over 60 who were already vaccinated more than five months ago in an effort to control its own surge in cases.
The White House has said that even though the US has begun sharing more than 110 million vaccine doses with the world, the nation has enough domestic supply to deliver boosters to Americans.
Australian Associated Press
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