By MIKE STOBBE and LAURAN NEERGAARD

ATLANTA (AP) — The Trump administration’s new vaccine advisers on Thursday endorsed this fall’s flu vaccinations for just about every American but threw in a twist: Only use certain shots free of an ingredient antivaccine groups have falsely tied to autism.

What is normally a routine step in preparing for the upcoming flu season drew intense scrutiny after U.S. Health Secretary Robert F. Kennedy Jr. abruptly fired the influential 17-member Advisory Committee on Immunization Practices and handpicked replacements that include several vaccine skeptics.

That seven-member panel bucked another norm Thursday: It deliberated the safety of a preservative used in less than 5% of U.S. flu vaccinations based on a presentation from an antivaccine group’s former leader — without allowing the usual public presentation of scientific data from the Centers for Disease Control and Prevention.

The preservative, thimerosal, has long been used in certain vaccines that come in multi-dose vials, to prevent contamination as each dose is withdrawn. But it has been controversial because it contains a small amount of a particular form of mercury.

Study after study has found no evidence that it causes autism or other harm. Yet since 2001, vaccines used for U.S. children age 6 years or younger have come in thimerosal-free formulas — including single-dose flu shots that account for the vast majority of influenza vaccinations.

The panel voted 5-1, with one abstention, that people ages 6 months and older get a flu vaccination this fall only using single-dose formulas that are thimerosal-free.

“There is still no demonstrable evidence of harm,” one adviser, Dr. Joseph Hibbeln, a psychiatrist formerly with the National Institutes of Health, said in acknowledging the panel wasn’t following its usual practice of acting on evidence.

But he added that “whether the actual molecule is a risk or not, we have to respect the fear of mercury” that might dissuade some people from getting vaccinated.

The ACIP, created more than 60 years ago, helps the CDC determine who should be vaccinated against a long list of diseases, and when. Those recommendations have a big impact on whether insurance covers vaccinations and where they’re available.

Kennedy has long held there was a tie between thimerosal and autism, and also accused the government of hiding the danger. Thimerosal was placed on the meeting agenda shortly after Kennedy’s new vaccine advisory was named last week.

Some public health experts contend the thimerosal discussion unnecessarily raised doubt in vaccines while possibly also making them more expensive and harder to get this fall.

At the panel’s meeting Wednesday, Chrissie Juliano, executive director of the Big Cities Health Coalition, lamented the ouster of the former ACIP panel and the agenda of the new one.

Her organization, which represents large city health departments, “is deeply concerned that many routine vaccines may soon become inaccessible or unaffordable for millions of Americans if ACIP makes changes based on ideology rather than science,” she said. “The stakes are simply too high to let that happen.”

Neergaard reported from Washington.

The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Department of Science Education and the Robert Wood Johnson Foundation. The AP is solely responsible for all content.