Recent upheaval at the U.S. Centers for Disease Control and Prevention involves political interference in vaccine policy decisions. Former CDC director Susan Monarez testified that Health Secretary RFK Jr. demanded blanket approval of altered vaccine guidelines and the firing of scientists, leading to her dismissal and staff resignations. The Advisory Committee on Immunization Practices (ACIP) voted to remove MMRV vaccine recommendations for children under 4 and postponed hepatitis B vaccine delay votes. Experts warn that such changes without solid scientific evidence could undermine public health and vaccine access.