In a move that has sent ripples through the U.S. public health community, the newly restructured federal vaccine advisory panel—handpicked by Health Secretary Robert F. Kennedy Jr.—convened last week to overhaul several longstanding immunization recommendations. The Advisory Committee on Immunization Practices (ACIP), now composed largely of individuals with reputations for vaccine skepticism, voted to limit the use of the combined measles, mumps, rubella, and varicella (MMRV) vaccine for young children and to shift the nation’s COVID-19 vaccination guidance from a universal recommendation to one based on individual choice.
The two-day session, held September 18-19, 2025, marked the first major policy outing for the Kennedy-appointed panel. The meeting was at times contentious and, according to Axios, exposed confusion among members over both procedural matters and the scientific evidence under discussion. Still, the panel’s decisions could have far-reaching implications for childhood immunization schedules and adult access to COVID-19 vaccines, especially in states that closely follow Centers for Disease Control and Prevention (CDC) guidance.
On Thursday, September 18, the ACIP voted 8-3, with one abstention, to stop recommending the MMRV combination shot for children under four years old. Instead, the panel advised that children receive separate MMR and varicella (chickenpox) vaccines. The rationale, as reported by the New York Post, was concern over a small but documented risk of fever-related seizures associated with the combined vaccine. "A very frightening experience," Dr. Cody Meissner, one of the committee members, said about febrile seizures, though he ultimately supported keeping the combined shot available. Data presented to the committee showed that 85% of parents already opt for separate shots for their child’s first immunization, suggesting the change aligns with current parental preferences.
However, the panel’s initial vote created the risk of a two-tiered system, as it conflicted with the policies of the federal Vaccines for Children (VFC) program, which provides free vaccines to families with limited means. After a second 8-3 vote, the ACIP decided to keep the existing MMRV recommendation unchanged for the VFC program, avoiding discrepancies in vaccine access based on income or insurance status.
The committee also delayed a decision on whether to stop recommending hepatitis B vaccines for newborns whose mothers are not infected, citing insufficient data and procedural confusion. Some members, including Meissner, argued that the vaccine is “absolutely safe” and should remain in use within 24 hours of birth, while others, such as Vicky Pebsworth of the National Vaccine Information Center, questioned whether the science is fully settled.
Friday’s session turned to COVID-19 vaccine policy, where the panel voted to weaken the federal government’s previous recommendation that all Americans aged six months and older receive yearly COVID-19 vaccinations. Instead, the committee said the decision should be made on a "shared clinical decision-making" basis—meaning individuals should consult with their healthcare providers and decide for themselves. The panel did emphasize the continued benefits of COVID-19 vaccines for those at high risk of severe illness, but the move represents a significant departure from the universal recommendation that has been in place since the vaccines became widely available.
Medical professionals and public health organizations have voiced concern about these changes. According to Axios, some clinicians believe the ACIP’s actions risk destabilizing decades of progress in public health. "They're responding not to scientific signals but to the mob they're beholden to," said Amesh Adalja, a senior scholar at the Johns Hopkins Center for Health Security. "They need to score points with the anti-vaccine movement because that's ultimately who gave them power." Jason Goldman of the American College of Physicians called on the panel to clarify its process for vetting and discussing future vaccines, while Sean O'Leary, infectious disease chairman at the American Academy of Pediatrics, criticized the focus on "myths, anecdotes, case series, case reports ... they were not focused at all on the actual science."
CDC acting director Jim O’Neill, who took over in August after Kennedy dismissed former director Susan Monarez, must still approve the ACIP’s recommendations before they become official policy. O’Neill, however, commended the committee for "bringing overdue scientific debate on vaccination to the American people." The Department of Health and Human Services (HHS) also weighed in, noting that the MMRV vaccine doubles the risk of seizures in toddlers compared to separate vaccinations, but does not offer additional protection against chickenpox. HHS further clarified that ACIP’s emphasis on individual decision-making could mean consulting with a doctor, nurse, or pharmacist, and that the recommendations, if finalized, would continue to allow insurance coverage for all recommended vaccines.
Insurance coverage remains a critical concern. America’s Health Insurance Plans (AHIP), a national association representing more than 200 million Americans, confirmed it would continue to cover all ACIP-recommended vaccines without cost-sharing through the end of 2026, including updated COVID-19 and flu shots. The Department of Health and Human Services has pledged to review insurance coverage implications before finalizing the new recommendations, given that insurers often follow ACIP guidelines to determine which vaccines are covered at no cost.
The composition of the ACIP itself has been a lightning rod for controversy. Earlier this year, Kennedy dismissed all 17 existing members, describing the move as a "clean sweep" to "re-establish public confidence in vaccine science." Critics, however, accuse Kennedy of stacking the panel with anti-vaccine advocates. As reported by Axios, some of the new members have been openly critical of vaccines and accused of spreading misinformation. Five additional members were appointed just days before the September meeting.
The ousting of former CDC Director Susan Monarez has drawn particular scrutiny. Monarez told senators she was fired for refusing to pre-approve ACIP recommendations without reviewing the evidence. "I refused to do it because I have built a career on scientific integrity," she testified. Kennedy has denied her claim, but the episode has fueled concerns about the politicization of vaccine policy and the erosion of scientific standards within federal health agencies.
Some clinicians and legal experts now argue that the ACIP has lost its legitimacy. Dorit Reiss, a law professor at UC Law San Francisco, commented that the panel "cannot be revived ... the rookie, biased, uninformed committee destroyed its legitimacy." Others suggest that licensed physicians should rely instead on guidance from established medical associations, such as the American Academy of Pediatrics and the American College of Obstetricians and Gynecologists.
As the nation awaits the CDC’s final decision on these recommendations, one thing is clear: the debate over vaccine policy, public health, and the role of scientific evidence in federal decision-making is far from settled. The changes proposed by Kennedy’s ACIP may shape the landscape of American immunization policy for years to come, with consequences that reach well beyond the walls of the committee’s meeting room.
