In June 2025, the U.S. Centers for Disease Control and Prevention (CDC) convened one of the most consequential—and controversial—meetings in its history. The Advisory Committee on Immunization Practices (ACIP), long a pillar of evidence-based vaccine policy, met for the first time under its new membership, hand-selected by Trump-Vance Health and Human Services (HHS) Secretary Robert F. Kennedy Jr. The overhaul—executed just weeks before the meeting—saw all 17 expert members fired and replaced with eight newcomers, many of whom lack qualifications in immunology, vaccinology, or public health. Several have direct ties to anti-vaccine organizations.
The result: an unprecedented two-day spectacle in which disinformation was given a platform, decades of scientific consensus were sidelined, and new vaccine policy decisions were made without credible evidence—raising urgent concerns among medical leaders, public health advocates, and global immunization partners.
A Meeting Unlike Any Other
The June 25–26 ACIP meeting unfolded in a deeply altered environment. The committee, once composed of infectious disease specialists, pediatricians, and public health scientists, now includes individuals with little to no expertise in vaccines. At least two members have testified in litigation against vaccine manufacturers. One speaker, Lyn Redwood, a former leader of the anti-vaccine group Children’s Health Defense, presented discredited claims about vaccine preservatives—citing a study that does not exist. The presentation was reportedly generated using AI.
Veteran observers, including public health professionals who have followed ACIP for decades, were stunned. “This was not a scientific meeting,” said one former CDC adviser. “This was a platform for misinformation dressed up as deliberation.”
Decisions Without Data
Despite the absence of new evidence or safety signals, the new ACIP voted to recommend that all Americans—including children, pregnant women, and adults—receive only thimerosal-free flu vaccines. Thimerosal, a preservative used in a small minority of multi-dose flu vials, has long been found to be safe. No study has ever linked it to harm, and it is not even present in most U.S. vaccines.
“You can have an AI-generated opinion piece presented by a citizen with no advanced degree… just say, ‘I’ve got all this stuff here and I think thimerosal should be out.’ No data. No subject matter expert. No working group. This has nothing to do with science or safety whatsoever,” commented infectious disease specialist Daniel Griffin, MD, PhD on This Week in Virology.
Committee members also signaled a willingness to revisit the entire childhood vaccine schedule and the hepatitis B birth dose—both long-standing targets of anti-vaccine activists. The American Academy of Pediatrics (AAP) responded by boycotting the meeting entirely and vowing to issue its own evidence-based immunization recommendations going forward.
“This vote was a greatly consequential milestone in ACIP’s transformation into an official organ of Kennedy’s anti-vaccine propaganda machine, rendering the committee completely devoid of value in the practice of medicine,” noted Amesh Adalja, MD in MedPage Today.
Dangerous Precedent, Global Consequences
The consequences of ACIP’s June meeting extend far beyond domestic flu policy. Although thimerosal is no longer used in most U.S. vaccines, it remains vital to global immunization programs due to its cost-saving role in multi-dose vials. U.S. vaccine guidance influences purchasing and policy decisions abroad. The new ACIP vote could erode confidence in thimerosal-containing vaccines globally, disrupt supply chains, and drive up costs for low- and middle-income countries—jeopardizing access to vaccines against influenza, tetanus, and diphtheria.
At the same time, RFK Jr. announced the U.S. would renege on its $1.2 billion commitment to Gavi, the Vaccine Alliance, undermining vaccination programs worldwide. In nations already facing resurgent measles and polio outbreaks, this funding withdrawal could prove catastrophic.
A Blow to Public Trust
Perhaps most alarming is the erosion of trust in the institutions responsible for safeguarding public health. CDC staff were reportedly sidelined during parts of the meeting. Background materials, including a CDC-authored document affirming thimerosal’s safety, were pulled from the public record without explanation. New ACIP members repeatedly misunderstood—or openly challenged—basic scientific principles, including how vaccines are tested and monitored.
“The public depends on the CDC and ACIP to provide clear, evidence-based guidance,” said Dr. Sean O’Leary of the AAP’s infectious disease committee. “What we witnessed was a distortion of that process. This is a crisis of governance as much as science.”
Six former ACIP chairs issued a rare joint statement warning that the U.S. is “witnessing a dismantling of the systems that develop, license, recommend, and monitor vaccines,” calling on Congress to intervene.
What’s at Stake for the Nation
Beyond the chaos of the June meeting lies a more fundamental threat. Immunization programs are not just medical protocols—they are cornerstones of national health security. When public confidence in vaccines collapses, diseases once vanquished can return. When scientific governance is replaced by ideology, the nation loses its ability to prepare for and respond to outbreaks. This is not speculative.
The ACIP meeting occurred as measles cases rise across more than 35 states, COVID-19 continues to send patients to hospitals, and RSV remains a serious seasonal burden. These overlapping outbreaks are straining health systems, crowding emergency departments, delaying care, and exhausting frontline staff. Yet ACIP failed to convene its COVID-19 vaccine working group or vote on recommendations for the fall season—decisions that directly affect whether insurers will cover the updated vaccines and whether providers can order, distribute, and administer them on time. The next ACIP meeting isn’t scheduled until October, and COVID-19 isn’t even on the agenda. The absence of timely, evidence-based guidance puts everyday Americans at risk of facing out-of-pocket costs, missed protection, and preventable illness—all while the healthcare system remains under pressure.
A Call to Action
The June 2025 ACIP meeting was not just a deviation from scientific norms—it was a turning point. The health of the American people, and the integrity of U.S. vaccine policy, now hang in the balance.
Professional societies, insurers, clinicians, and public health agencies are beginning to chart alternative paths—creating new coalitions, reaffirming evidence-based recommendations, and seeking to insulate health guidance from political manipulation. But restoring trust will require more: transparency, oversight, and a national recommitment to science.
Because in the face of resurgent diseases and coordinated disinformation, silence is complicity—and the cost of inaction will be measured in lives.
Sources & Further Reading
- This Weeek in Virology (TWiV): Clinical Update #1230
- CIDRAP: Fallout from ACIP Meeting
- American Academy of Pediatrics: We Will Publish Our Own Vaccine Schedule
- STAT: Former ACIP Chairs on the Vaccine Crisis
- Your Local Epidemiologist: ACIP Briefings
- Pandora Report: ACIP After the Overhaul
- MedPage Today: ACIP’s First Day
- ARS Technica: Junk Data and Flu Policy