Website Update Sparks Rapid Backlash
The CDC revised key sections of its website on Wednesday, adding language that questions decades of vaccine safety research. The new wording suggests scientists have not fully ruled out a link between vaccines and autism. Experts warn that this framing misleads the public and undermines clear scientific consensus.
New Phrasing Fuels Unnecessary Doubt
The site now claims that saying “vaccines do not cause autism” is not evidence-based because studies cannot exclude every possibility. Researchers say this is a well-known tactic used to create skepticism. Alison Singer of the Autism Science Foundation explains that no study can prove an absolute negative. She says scientists rely on a large body of consistent findings.
Singer stresses that overwhelming evidence shows vaccines do not cause autism. Her foundation notes that no environmental factor has been studied more intensely than vaccines and their components.
Medical Leaders Reject the Claims
Pediatrician Paul Offit sharply criticizes the new CDC language. He says the logic behind it could be applied to almost anything. He argues it could even imply ordinary foods may cause autism, since that idea also cannot be “disproven.” A federal health spokesperson says the agency aims to align the website with the strongest scientific evidence.
A senior FDA commissioner recently told Sanjay Gupta that he does not believe vaccines cause autism. He says no medical product is perfectly risk-free and warns that rigid language damages trust.
Extensive Research Shows No Link
The updated CDC page claims that studies supporting a link have been dismissed. This is false. Research claiming a connection has been discredited or exposed as fraudulent. Meanwhile, many credible studies show no relationship.
A major Danish study from 2019 followed more than 650,000 children. Roughly 6,500 developed autism. Researchers found no difference in autism rates between vaccinated and unvaccinated children. That held across many variables, including family history and exposure to other vaccines. The authors concluded the MMR vaccine does not increase autism risk.
The CDC’s update does not cite this major study. It relies on older reviews and raises questions about aluminum in vaccines. A 2025 Danish study found no link between aluminum and 50 medical conditions, including autism. Yet the revised page still claims more investigation is needed.
The site also refers to a federal review of autism causes. Singer calls this a misuse of resources and says strong genetic evidence already explains most cases.
The main page still features the line “Vaccines do not cause autism.” A footnote says it stays due to an agreement made during the health secretary’s confirmation process.
A senator later confirmed discussing the issue with the secretary. He says parents need straightforward information and emphasizes that vaccines for childhood diseases remain safe and do not cause autism.
Experts Warn of Growing Public Health Harm
Vaccine scientist Peter Hotez says the updated page repeats ideas disproven many times. He points to past misinformation on MMR vaccines, thimerosal, and aluminum. He calls the new content dangerous and says it must be removed.
A former CDC immunization chief wrote that the edits are “a national embarrassment.” He says staff were blindsided and that these moves weaken trust in public health. Pediatric specialists warn that such changes could drive vaccination rates even lower.
Political Pressure Drives the New Direction
The website edits match broader efforts by the administration to challenge long-standing vaccine policy. The health secretary has brought in advisers with records of opposing vaccines. Some have faced sanctions or criticism for flawed research. They now analyze federal data to support claims of hidden vaccine risks.
Routine childhood vaccination rates continue to fall across the country. Outbreaks of measles and whooping cough are rising. CDC disease trackers warned this week that the United States may soon lose its status as a nation free of continuous measles transmission.
