The cancellation plays into fears among scientists who worry that Robert F. Kennedy Jr. will use his position as health secretary to sow doubts about vaccines.

The vaccine meeting canceled by the FDA is the second federal vaccine panel meeting Trump administration officials have canceled since RFK Jr. took over HHS.

A meeting of a committee which advises the U.S. Food and Drug Administration on vaccine policy has been canceled, a committee member told Reuters, the second such disruption to a federal vaccine advisory panel since Robert F.