RFK Jr.’s vaccine committee votes against rarely used flu shot preservative, backs new RSV shot

The Centers for Disease Control and Prevention‘s panel of vaccine advisers voted Thursday in their first official move after Health and Human Services Secretary Robert F. Kennedy Jr. fired the committee’s previous experts and replaced them with his own picks.

A majority of the committee approved updated recommendations for a new shot for respiratory syncytial virus, or RSV, and voted to urge Americans to avoid a small number of flu vaccines that use the preservative thimerosal despite evidence of its safety.

Votes by the panel are closely watched by health authorities because they are tied to federal policies and programs that enable access to vaccines, including requirements for insurance coverage and funding to provide shots for uninsured children. 

Other vaccines were also being discussed by the panel, but not voted on, including those for COVID-19, measles, chikungunya and anthrax.

Kennedy’s new committee also announced Wednesday that it would start a renewed review of all recommended pediatric vaccines, over fears about the “cumulative effect” that the shots could be having on children. That includes weighing changes to recommendations for hepatitis B and measles vaccines given early in life.

The American Academy of Pediatrics, or AAP, denounced the move as sowing distrust in safe and effective immunizations, and warned Wednesday against curbing hepatitis B recommendations.

“Secretary Kennedy has given this committee a clear mandate to use evidence-based medicine when making vaccine recommendations, and that is what we will do. Vaccines are not all good or bad,” Dr. Martin Kulldorff, the panel’s chair, said Wednesday.

Flu vaccines and thimerasol

The panel’s majority vote to recommend against flu vaccines with thimerosal is unlikely to impact many Americans, since the mercury-based preservative is already rarely used in the shots. During the 2024-2025 season, 96% of all influenza vaccines in the U.S. were thimerosal-free, according to the CDC.

“If we want to have confidence in vaccines, and we want to promote people taking vaccines, we should remove this mercury-containing preservative from the seasonal influenza,” said Kulldorff. 

One of the panel’s advisers, Dr. Cody Meissner of Dartmouth University, questioned why the committee was reopening an old issue that had previously been addressed by health authorities, potentially undermining a heavily studied vaccine ingredient.

“The ACIP makes recommendations based on scientific evidence, as much as possible, and there is no scientific evidence that thimerasol has caused a problem,” Meissner said, who was the only panelist to vote against the change. 

Thimerosal has been added to vaccines since the 1930s to help prevent bacteria in multi-dose vials of vaccine. It contains a form of mercury called ethylmercury, which is different from the methylmercury found in some seafood.

“Ethylmercury is excreted much more quickly from the body. It is not associated with the high neurotoxicity that methylmercury is,” Meissner said.

The U.S. Food and Drug Administration states that a “robust body of peer-reviewed scientific studies conducted in the U.S. and other countries support the safety of thimerosal-containing vaccines.”

Anti-vaccine groups have falsely tied thimerosal to autism. However, well-designed studies have found no evidence that thimerosal causes autism.

CDC officials told CBS News they saw the meeting as an early test case demonstrating how Kennedy has tightened his grip over the federal vaccine recommendations process and eroded its credibility. 

Multiple liaison members of the panel, representing outside groups, objected to the committee bypassing the rigorous, usually monthslong CDC systemic review process that studies evidence on the need, impact and feasibility of new recommendations. Some worried re-debating settled science could contribute to unnecessary fears or doubts around vaccines that have long been considered safe.

“This selective use of data and omission of established science undermines public trust and fuels misinformation. The science on thimerosal is settled, and the rhetoric being used to suggest otherwise is misleading and harmful,” Dr. Sean O’Leary, head of the AAP’s infectious diseases committee, said in a statement.

Instead, the vote was based mainly on a presentation by Lyn Redwood, the former head of a group founded by Kennedy that has lobbied against vaccine authorizations and requirements. Redwood has been hired to work in the agency’s vaccine safety office, though she said Thursday she was speaking only as a private citizen.

“I think it’s inappropriate to dismiss a presentation, just because the person does not have a PhD or an MD. There are a lot of knowledgeable people who we would like to hear from, and we want to hear from a variety of viewpoints,” Kulldorff said.

Ahead of the meeting, the CDC removed a review the agency previously posted on its website that debunked claims about how the preservative could cause autism or other neurodevelopmental disorders.

“My understanding is that article was not authorized by the Office of the Secretary, and has been removed consequent. I’m sure that the Office of the Secretary will make note of your comment,” panelist Dr. Robert Malone said.

Malone was responding to a question from Phyllis Arthur of Bio, a trade group that represents vaccinemakers, who had called for the CDC’s evidence review to be restored to the website. 

Molly Howell of the Association of Immunization Managers worried the move could also impact plans for a potential pandemic influenza vaccine, which currently rely on the potential use of the preservative.

“Future meetings of ACIP and CDC will have to consider those things,” Kulldorff said.

RSV shot

An RSV vaccine during pregnancy and another antibody shot called clesrovimab that can be given to newborns have previously been approved by the Food and Drug Administration and recommended by the CDC to prevent the disease.

The committee Thursday voted by a majority — five in favor, two against — to recommend a shot for newborns, branded as Enflonsia by Merck, adding another option to the already approved immunizations.

Two of the panel’s new members — Retsef Levi, an operations management professor at the Massachusetts Institute of Technology, and Vicki Pebsworth, the research director of a group focused on preventing vaccine injuries and deaths — voted against recommendations for the shot.

Pebsworth said she worried about coadministration of the shot with other childhood vaccines, despite data presented by the CDC’s Vaccine Safety Datalink showing that RSV antibody shots being given alongside other vaccines are not resulting in a safety risk.

Levi said that he was uncomfortable with clinical trial data he claimed suggested that deaths could be more frequent after use of the shots. He cited his experience as a parent, saying that “as a father, I can feel that I would be concerned.”

“I don’t feel this is ready to be administered to all healthy babies. I think we should take a more precautionary approach to this,” Levi said.

That was at odds with reviews by the CDC and FDA, which did not turn up evidence of this risk. An FDA official told the panel that the death rates — 0.3% after the shot versus 0.2% without — were not significant, and that careful reviews of the deaths concluded that their causes were not related to the drug.

Meissner disagreed with Levi, warning that 80% of children hospitalized with RSV are healthy with no underlying conditions. 

Meissner had previously participated in the deliberations of the committee’s work group as an outside adviser, before Kennedy purged its voting members.

“The work group has spent an enormous amount of time, the FDA has spent an enormous effort looking at safety and efficacy, and it is simply not an issue here,” he said.