CDC Breaks from Medical Consensus on Vaccine-Autism Link (1)

The US Centers for Disease Control and Prevention updated a page on its website to suggest vaccines may cause autism, rejecting longstanding medical consensus on the topic and advancing a campaign from Health and Human Services Secretary Robert F. Kennedy Jr.

The website change is the latest flash point in a battle between public health experts and advocates of the Make America Healthy Again movement who’ve long pushed debunked claims about vaccines. Kennedy has clashed with CDC staff, medical associations and scientists over his views on shots.

Late Wednesday, the CDC pagewas updated to say scientific research hasn’t ruled out the possibility that shots given to infants lead to autism. An asterisk was also added to the phrase “vaccines do not cause autism.”

“Studies supporting a link have been ignored by health authorities,” the website says.

One pediatrician in Austin was so surprised by the changes that she wondered if the CDC website had been hacked.

The changes mean doctors can “no longer rely on the CDC website for evidence-based information,” said the doctor, Ari Brown, in an email.

To justify the changes, the CDC casts doubt on major studies showing no link between the MMR vaccine and autism, including a widely cited 2002 Danish study.

Robert F. Kennedy Jr.

Photographer: Kayla Bartkowski/Bloomberg

Kennedy has long been focused on autism and shots, and his stance toward links the between the two was a point of controversy during his confirmation hearings. Kennedy promised Louisiana Senator Bill Cassidy that he wouldn’t remove CDC language that debunked the link between immunizations and autism. A footnote now states the phrase “vaccines do not cause autism” hasn’t been removed entirely due to the agreement with Cassidy, the chair of the Senate Committee on Health, Education, Labor and Pensions.

HHS spokesman Andrew Nixon defended the change, saying the agency is “updating the CDC’s website to reflect gold standard, evidence-based science.” The website was also updated to include links to additional research.

Despite years of study, there is no conclusive evidence that vaccines cause autism. The CDC has long stood behind its childhood vaccination schedule, saying it’s a critically important public health tool that stops the spread of dangerous preventable diseases and that the benefits outweigh the risks.

Still, Americans have a more negative view toward shots than they have in years. Only 78% of Republicans in an October survey said the benefits of the measles, mumps and rubella shot outweigh the risks, according to a survey from Pew Research Center released this week. In 2016, 91% of Republicans gave the same answer.

HHS has launched a comprehensive assessment of the causes of autism, including investigations on “plausible biologic mechanisms and potential causal links,” the CDC website says.

During the hearing for his nomination as health secretary, Kennedy refused tosay outright that vaccines don’t cause autism. Cassidy pointed to a study of 1.25 million children that showed the measles vaccine isn’t associated with autism.

Cassidy’s office did not immediately respond to repeated requests for comment.

It’s not the first time Kennedy has gone against his promises to Cassidy. In June, Kennedy fired the CDC’s 17-member vaccine advisory panel and picked its replacements — many who are Covid vaccine skeptics. The panel subsequently voted to remove the preservative thimerosal in multidose vaccines, an ingredient long targeted by the anti-vaccine movement.

The draft agenda for a December meeting lists a discussion on other vaccine ingredients and a review of the childhood vaccination schedule.

(Updates with medical reaction, background from fifth paragraph)

--With assistance from Robert Langreth.

To contact the reporters on this story:
Jessica Nix in New York at jnix20@bloomberg.net;
Rachel Cohrs Zhang in Washington at rzhang698@bloomberg.net

To contact the editors responsible for this story:
Cynthia Koons at ckoons@bloomberg.net

Kelly Gilblom, Magan Crane

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