WASHINGTON (AP) — Just one month ago, President Joe Biden and his health advisers announced big plans to soon deliver a booster shot of the coronavirus vaccine to all Americans. But after campaigning for the White House on a pledge to "follow the science," Biden found himself uncharacteristically ahead of it with that lofty pronouncement.

Some of the nation's top medical advisers on Friday delivered a stinging rebuke of the idea, in essence telling the White House: not so fast.

A key government advisory panel overwhelmingly rejected Biden's plan to give COVID-19 booster shots across the board...