Dr. Fiona Havers is influential among researchers who study immunizations. The wholesale dismissal of the agency’s scientific advisers crossed the line, she said.

Dr. Fiona Havers is influential among researchers who study immunizations. The wholesale dismissal of the agency’s scientific advisers crossed the line, she said.

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.