Overview

• ACIP voted 8–3 to advise against the combined measles‑mumps‑rubella‑varicella shot for children younger than 4, with Dr. Robert Malone abstaining.
• CDC presenters cited a small, long‑recognized increase in febrile seizures after the first MMRV dose in toddlers, with no increased risk seen in older children.
• The action is advisory and will not take effect unless Acting CDC Director Jim O’Neill adopts it after HHS evaluates coverage implications.
• Core immunization guidance remains intact, with two MMR doses still recommended and MMRV still an option at ages 4–6, as many parents already choose separate MMR and varicella shots.
• Implementation may vary as California gains authority to set its own vaccine schedule and AHIP says members will cover vaccines under CDC recommendations in place as of Sept. 1 through 2026, amid criticism of recent ACIP appointments by HHS Secretary Robert F. Kennedy Jr.