Two long-planned vaccine meetings — one at the US Centers for Disease Control and another at the US Food and Drug Administration — have now been disrupted under the watch of US Health and Human Services Secretary Robert F.

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.

Epidemiologist Michael Osterholm, the head of the University of Minnesota Center for Infectious Disease Research and Policy, joined Morning Edition host Cathy Wurzer to talk about the implications of axing the meeting.