US grapples with whether to modify COVID vaccine for fall

U.S. health authorities are facing a critical decision: whether to offer new COVID-19 booster shots this fall that are modified to better match recent changes of the shape-shifting coronavirus.

Moderna and Pfizer have tested updated shots against the super-contagious omicron variant, and advisers to the Food and Drug Administration will debate Tuesday if it’s time to make a switch — setting the stage for similar moves by other countries.

“This is science at its toughest,” FDA vaccine chief Dr. Peter Marks told The Associated Press, adding that a final decision is expected within days of the advisory panel's recommendation.