Dr. Noel Brewer, a former ACIP member removed by Kennedy and a professor in the department of health behavior at the University of North Carolina Gillings School of Global Public Health, told ABC News that since the upheaval of the ACIP, vaccination has changed in the U.S. in a "fundamental" way and that the committee has "lost credibility."

The health and human services secretary and noted vaccine skeptic named a new panel to provide the guidance often used by states in setting school immunization requirements.

All 17 experts from the Advisory Committee for Immunization Practices who were replaced last month by Robert F. Kennedy Jr. called the health secretary's new picks "inexperienced and biased."