US Vaccine Panel Bars Combined Measles Shot for Young Children

Lead A CDC advisory committee voted on Thursday to remove guidance allowing the combined measles-mumps-rubella-varicella (MMRV) vaccine for children under four, citing heightened seizure risk and new political oversight.

Nut Graf The decision by the Advisory Committee on Immunization Practices (ACIP)-reconstituted by Health Secretary Robert F. Kennedy Jr.-reflects safety concerns over febrile seizures linked to the combined shot and marks a shift in U.S. childhood immunization policy amid leadership controversies.

Recommendation Change

• ACIP voted 8-3 to discourage use of MMRV in children aged 12-47 months, with one abstention.
• The move instructs providers to administer separate MMR and varicella vaccines for this age group.

Safety Concerns

• Data indicate the combined MMRV shot doubles the rate of fever-related seizures (7-8 per 10,000) compared to separate injections (3-4 per 10,000).
• ACIP members emphasized that febrile seizures, while generally benign, warrant policy adjustments to protect patient safety.

Political Context

• The panel comprises 12 advisors hand-picked by Kennedy after dismissing 17 previous members, intensifying scrutiny over the CDC’s independence.
• ACIP Chair Martin Kulldorff called for transparency and open debate amid vaccine policy disputes.

Program Implications

• The Vaccines for Children program will no longer cover MMRV for under-4s, though insurers must reimburse any February-2026 recommendations.
• Providers must update electronic order sets and parental guidance materials to reflect the separate dosing schedule.

Impact on Immunization

• Experts warn that separating shots could slightly lower adherence to the vaccination schedule, potentially impacting herd immunity.
• Public health officials stress enhanced communication strategies to maintain coverage rates above the 95% MMR target.