New guidance published by the US Centers for Disease Control and Prevention (CDC) suggesting vaccines may cause autism has been slammed by medical and autism advocacy groups.
A CDC webpage which previously stated there was no link between vaccines and autism was changed on 19 November.1
The page now reads, “The claim ‘vaccines do not cause autism’ is not an evidence based claim.”
The revised webpage—part of a resource aiming to provide the public with science backed information on health matters—goes on to say, “Scientific studies have not ruled out the possibility that infant vaccines contribute to the development of autism.” It says that historically the CDC and other federal health agencies have told the public that vaccines don’t cause autism to “prevent vaccine hesitancy.”
It adds that the health ministry has launched a comprehensive study of the causes of autism, including vaccines.
Leading medical research organisations and advocacy groups criticised the change and sought to remind the public that decades of research had established no link between autism and vaccines.
Susan Kressly, president of the American Academy of Paediatrics, said, “Since 1998 independent researchers across seven countries have conducted more than 40 high quality studies involving over 5.6 million people.
“The conclusion is clear and unambiguous: there’s no link between vaccines and autism.
“We call on the CDC to stop wasting government resources to amplify false claims that sow doubt about one of the best tools we have to keep children healthy and thriving: routine immunisations.”
Researchers have also highlighted that saying that no study has entirely ruled out the possibility that infant vaccines cause autism was not a logical argument.
“You can’t prove something never happens,” said Jake Scott, a professor at Stanford Medical School. “Scientists can’t prove vaccines never cause autism because proving a universal negative is logically impossible.”2
Advocacy groups published statements reminding the public that decades of rigorous research indicated the contrary to what the CDC was now claiming.
“The science is clear that vaccines do not cause autism. No environmental factor has been better studied as a potential cause of autism than vaccines,” the Autism Science Foundation said in a statement.3
Several former senior CDC officials—including the organisation’s former chief medical officer Debra Houry—said the change is the latest example of the growing politicisation of public health under President Donald Trump and vaccine sceptic health secretary, Robert F Kennedy Jr.
“Public health communication must be accurate, evidence based, and free from political distortion. Anything less erodes trust and puts lives at risk,” she said.
Changes to the CDC webpage come after a series of actions by Kennedy that have overhauled the agency.
CDC director Susan Monarez left in August, reportedly because of a disagreement over vaccine policy, and in June Kennedy dismissed all 17 members of the committee that advises the agency on vaccines, replacing them with his own nominees.
At least 600 employees across the CDC have been fired this year and senior officials have resigned, citing political interference in science.
Kennedy has also repeatedly suggested that childhood vaccines may be linked to autism, concerning experts who say the comments fuel misinformation and undermine trust in immunisation programmes critical to public health.
Demetre Daskalakis, who recently resigned as director of the CDC’s National Center on Immunization and Respiratory Diseases, described the changes to the website as “a national embarrassment.”
“The weaponisation of the CDC is getting worse. This is a public health emergency,” he said on X.4
The CDC’s online directory is intended to serve as an authoritative resource to inform the American public. Leading researchers have said, however, that in recent months the organisation can no longer be trusted to represent medical research because of growing political intervention in the agency.
As such, medical associations have begun publishing their own independent guidance in response.5
The controversy comes as the US recorded the highest number of measles cases in two decades. Public health experts say measles—along with other vaccine preventable diseases—are on the rise because of declining vaccination rates that are driven, in part, by misinformation surrounding jabs.6
