Adams, who served as surgeon general during the first Trump administration, said Kennedy's assertions about the efficacy of mRNA vaccines are "simply not true."

This was one in a continuing line of moves that have put Kennedy's vaccine skepticism into public policy, though scientists say the vaccines are safe.

Former U.S. Surgeon General Jerome Adams says the nation faces serious public health risks from Department of Health and Human Services (HHS) Secretary Robert F. Kennedy Jr.'s decision to end federal funding for mRNA vaccine development.