RFK Jr. wins his fight against rare, safe flu-shot ingredient thimerosal

Federal vaccine advisers installed by Health and Human Services Secretary Robert F. Kennedy Jr. have voted to effectively remove an ingredient from flu shots, achieving a longtime, controversial goal of anti-vaccine activists and illustrating how their priorities are becoming official government guidance.

The vote to no longer recommend influenza vaccines that contain the preservative thimerosal, based on the presentation of a single vaccine critic, is likely to have limited impact because the vast majority of flu shots are thimerosal-free.

But it would probably make the shots more expensive and harder to receive in parts of the country, public health experts said, and showed the panel’s willingness to disregard scientific evidence.

Those experts were surprised that Kennedy’s newly reformulated Advisory Committee on Immunization Practices (ACIP) abruptly added thimerosal to the agenda of its first meeting because they considered the issue resolved decades ago.

Staff at the Centers for Disease Control and Prevention prepared a report, later taken offline, which analysed decades of evidence to conclude the preservative is safe and not linked to conditions such as autism.

But Kennedy, the founder of the anti-vaccine advocacy group Children’s Health Defense, has long criticised the use of thimerosal because it metabolises into a form of mercury in the body that he says is dangerous. Kennedy edited a 2015 book aimed at persuading the CDC to remove thimerosal in any vaccines.

In a lengthy X post Tuesday, Kennedy decried the use of thimerosal and criticised a media outlet for describing it as safe.

Now Kennedy will be able to enact that ban and is upending other vaccine policies once considered bipartisan and stable, even as administrations changed.

Until a CDC director is confirmed to sign off on the panel’s recommendation, Kennedy has the authority to make the final decision.

“The members of this committee are respected experts who take their responsibility to public health seriously,” HHS spokesman Andrew Nixon said. “What they did today is what Secretary Kennedy appointed them to do, which is review the evidence, debate it with scientific rigor, and deliver recommendations rooted in data and medical integrity. The public deserves nothing but this.”

Some ACIP members appointed by Kennedy, after he fired the entire panel in early June, argued that the use of thimerosal undermines public confidence in vaccination because of concerns about mercury.

In contrast, Cody Meissner, a pediatrician and infectious diseases expert who was the only panel member to vote no, argued that the move would limit the availability of flu shots.

“The risk from influenza is so much greater than the nonexistent, as far as I know, risk from thimerosal,” he said.

Multi-dose vials are easier to store and use for mass vaccination events than the single-dose counterparts.

Public health experts said rural medical facilities and safety-net systems could face potential shortages if they remove those vaccines, although an FDA representative at the meeting said there would be enough supply of single-dose shots to make up for the shortfall. Multi-dose vials are considered less expensive because they reduce waste and require less space to store.

The vaccine panel also said Wednesday that it would examine the cumulative effect of the childhood vaccine schedule and reevaluate hepatitis B immunisation recommendations, moves sought by anti-vaccine activists that could alter how and when the nation’s children receive shots.

ACIP recommendations determine who should receive a vaccine and when and whether vaccines must be covered by health insurance and distributed through a federal program for children.

David Margolius, director of public health for the city of Cleveland, said Kennedy is wasting time revisiting settled science. Margolius said the nation should be able to focus on smoking cessation and eliminating lead poisoning - not worry about measles outbreaks amid the vaccine distrust that Kennedy is fanning.

“He’s basically opened the door for public health problems that have been dealt with decades ago to come back into the picture,” Margolius said.

‘Cherry-picking data’

The panel’s vote to remove thimerosal followed a presentation from Lyn Redwood, a former leader of Kennedy’s anti-vaccine group who has been hired by HHS to work with the CDC’s vaccine safety office.

Redwood is not a physician and does not have a doctorate degree. Such presentations are usually reviewed by experts on the committee’s work groups that spend months researching the data and preparing a detailed cost-benefit analysis, according to liaison members to the ACIP, former members and CDC staff.

“They have just blown up that whole process by moving forward on a vote like this,” said Fiona Havers, a former CDC senior scientist who resigned last week because she did not have confidence data would be used objectively to set vaccine policy.

Redwood told the panel “thimerosal was grandfathered for use without adequate safety testing” and described mercury as “the third most toxic element”.

Her presentation was filled with inaccuracies and misleading statements, medical experts said.

“This has all been debunked many times,” said James Campbell, vice chair of the infectious diseases committee for the American Academy of Pediatrics. “She is cherry-picking data and presenting junk science to sow distrust in vaccines.”

Redwood seemed to conflate ethylmercury and methylmercury, according to the experts. When used in vaccines, thimerosal is metabolised into ethylmercury in the body, which is vastly different from methylmercury, which can be found in fish.

The levels of ethylmercury in vaccines have been found to be safe, while high levels of methylmercury can cause childhood developmental damage, according to public health authorities.

Redwood’s presentation also originally contained the citation of a study that did not exist, CNN reported.

Thimerosal was added to some vaccines decades ago to prevent bacterial contamination in multi-dose vials.

By the early 2000s, thimerosal had been removed or reduced to trace amounts in most childhood vaccines, with manufacturers increasingly using single-dose vials that did not require preservatives. It remains in some multi-dose influenza vaccines, according to the CDC, but the overwhelming majority are thimerosal-free.

Thimerosal has been at the heart of false claims that vaccines can cause autism, a link that Redwood implied in a response.

Meissner, the panelist whom public health advocates consider more mainstream on routine immunisation, strongly disagreed with Redwood’s presentation.

“The ACIP makes recommendations based on scientific evidence as much as possible, and there is no scientific evidence that thimerosal has caused a problem,” he said.

The vote is a culmination of Kennedy’s years of advocacy against thimerosal.

“This particular kind of vaccine, the multi-dose vial, is going to children, little children, it’s destroying their brains,” Kennedy said in a July 2023 podcast appearance. “I believe my belief is strongly grounded in science.”

Concerns over the new panel

The two-day gathering of the overhauled immunisation committee has allowed vaccine skeptics on the panel to give a common message that Kennedy has repeatedly stated: Too many shots may overwhelm children’s immune systems, and exposure to ingredients can build up over time and cause harm.

Medical and public health experts said those claims have been repeatedly investigated with no signs of concern.

The American Academy of Pediatrics refused to take part in the proceedings as it normally does, saying the committee has drifted from its focus on science, evidence and public health.

In a joint statement after their meeting, the new vaccine advisers said they are answering the call to establish confidence in the scientific process.

“This committee strongly supports the use of vaccines, and other countermeasures, predicated on evidence-based medicine, including rigorous evaluation and expansive credible scientific data, for both safety and efficacy,” they said.

Medical experts were alarmed at how panelists approached several of the questions Thursday.

Robert Malone described 250 pediatric flu deaths in the most recent flu season - the highest in 15 years - as “modest.”

“We need much more involvement by people who know these diseases, work with them, are clinically involved,” said Jesse Goodman, a Georgetown University professor of medicine who previously served as the Food and Drug Administration’s top vaccine regulator.

“If a bunch of people don’t take a vaccine that FDA has reviewed to the end of the Earth, and has shown is safe and effective - like if somebody doesn’t get pneumonia or meningitis vaccine - because of this overall tainting of all vaccines, people will die.”

In another unusual move, Martin Kulldorff, the panel chair, gave a presentation to his fellow members to highlight the known risks of a combination measles, mumps, rubella and chicken pox vaccine, known as MMRV.

Pediatricians said the rare and benign side effects were being exaggerated to undermine confidence in vaccines.

Public health advocates credited the panel for voting 5-2 to recommend a monoclonal antibody treatment that acts as an immunisation to protect healthy babies from getting the respiratory illness RSV, the leading cause of hospitalizations in infants in the United States. But the discussion leading up to the vote raised concerns.

Panel member Retsef Levi, a professor of operations management who became prominent for his criticism of mRNA coronavirus vaccines, asked repeatedly about a small number of deaths in clinical trials. As the father of six children, Levi said he would have concerns about using the product in a healthy infant.

Experts from CDC and the Food and Drug Administration, which reviewed the data extensively before licensing it, said there was nothing concerning to suggest the product caused the deaths.

The vote on the preventive product for RSV also showed the panel’s unfamiliarity with the recommendation process. Some members appeared confused and did not seem to understand they were also required to take a second, separate vote to add the immunization to the federal program that provides free vaccine for about half the children in the United States.

Caitlin Gilbert and Rachel Roubein in New York and Washington contributed to this report.

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