Robert F. Kennedy Jr.’s decision to overhaul a key committee on vaccine policy has left the country’s vaccine infrastructure “critically weakened,” former members of the group said in a piece published in JAMA on Monday.

A senior scientist at the U.S. Centers for Disease Control and Prevention has resigned, warning that changes in leadership may weaken the country's vaccine program.

State leads the way in allowing the health department to rely on a high-profile physicians group’s recommendations, not just the CDC, but no guidance has been changed.