WATCH: White House COVID task force holds briefing

WASHINGTON — More than 400,000 Americans got Pfizer booster shots last weekend through local pharmacies in the opening days of the U.S effort to provide more protection for vulnerable populations.

Watch the briefing in the player above.

White House COVID-19 coordinator Jeff Zients says an additional 1 million people have scheduled booster shots for the coming weeks. He adds: “We’re off to a very strong start with the booster campaign.”

As many as 25 million people qualify for the third dose of the Pfizer shot, which was authorized last week for those 65 or older, those with pre-existing conditions or facing an elevated risk at their workplace.

U.S. officials say their primary focus is ensuring the roughly 25 percent of eligible Americans who have yet to get their first shot do so.

Dr. Rochelle Walensky, the director of the Centers for Disease Control and Prevention, says a major priority is the vaccination rate among pregnant women, which stands at 30 percent nationally and at 15 percent among Black pregnant women. She encouraged them to seek out vaccinations, saying data shows they’re safe for mother and baby and can prevent needless illness or death.

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