The US Centres for Disease Control and Prevention has rewritten its official webpage on vaccines and autism. The agency now states that claiming vaccines do not cause autism is “not an evidence-based claim.” This represents a dramatic reversal from decades of public health messaging and has ignited fierce debate across the medical community.
Figure 1: Centres for Disease Control and Prevention (CDC) headquarters in Atlanta
The CDC vaccine autism update appeared on the agency’s website on 19 November 2025. Scientific information was replaced with language suggesting studies have not ruled out the possibility that infant vaccines cause autism. The webpage also claims that studies supporting a link between vaccines and autism have been ignored by health authorities.
CDC Vaccine Guidance Controversy Sparks Medical Community Backlash
The change has drawn immediate criticism from paediatricians and vaccine experts. Dr Sean O’Leary, head of the American Academy of Paediatrics’ infectious diseases committee, called the update “madness” during a media briefing. He emphasised that autism is among the most studied childhood conditions globally.
The Autism Science Foundation issued a statement describing itself as “appalled” by the CDC vaccine guidance controversy. President and co-founder Alison Singer explained that scientific studies cannot prove that something does not cause something else. Instead, researchers must point to the preponderance of evidence across multiple conclusive studies.
“No environmental factor has been better studied as a potential cause of autism than vaccines,” the Autism Science Foundation stated. This includes vaccine ingredients as well as the body’s response to vaccines.
The Science Behind Autism Vaccine Guidance 2025 Standards
One of the largest studies examining this question was published in 2019. Researchers in Denmark enrolled more than 650,000 children born between 1999 and 2011. They followed participants from age one until the end of August 2013.
Figure 2: Child receiving vaccine
Roughly 6,500 children were diagnosed with autism during the study period. When researchers compared those who received the MMR vaccine with those who did not, they found no significant difference. This held true across multiple factors, including siblings with autism and other vaccine exposures.
The study strongly supports that the MMR vaccine does not increase autism risk. However, this research is not cited on the CDC’s updated state of the evidence page. Instead, the page mentions older evidence reviews and raises questions about aluminium in some vaccines.
Political Pressure Shapes CDC Vaccine Autism Update Process
The main heading on the page states “Vaccines do not cause Autism”, but includes an asterisk. The footnote directs readers to an agreement with Senator Bill Cassidy, chair of the US Senate Health, Education, Labour and Pensions Committee. The language would remain on the CDC website per this commitment.
This appears to reference a promise made by Health and Human Services Secretary Robert F Kennedy Jr during his confirmation process. Kennedy, a longtime anti-vaccine activist, assured Cassidy that language pointing out that vaccines do not cause autism would not be removed.
Figure 3: Robert F. Kennedy Jr
Senator Cassidy told CNN he had spoken with Kennedy following the changes. In a statement posted on X, Cassidy said vaccines for measles, polio, hepatitis B and other childhood diseases are safe and effective. “Any statement to the contrary is wrong, irresponsible, and actively makes Americans sicker,” he wrote.
How CDC Vaccine Guidance Controversy Misrepresents Research
Scientists and doctors have accused the CDC of cherry-picking studies that raise doubt about vaccine safety. Dr Jake Scott, an infectious diseases specialist at Stanford Medicine, said the agency is taking evidence of safety and pretending it shows uncertainty.
The CDC webpage points to a large Danish study from July 2025. The research found that aluminium exposure from vaccines during the first two years of life was not associated with increased rates of neurodevelopmental disorders. The study examined more than 1.2 million children over roughly two decades.
However, the CDC highlights a supplementary figure suggesting increased Asperger’s syndrome risk in a tiny subset of children. Scott described this as a “statistical blip.” When testing 50 different conditions, a couple of outliers appear just by pure chance.
The webpage also cites two reports from the Institute of Medicine from 1991 and 2012. These reports actually rejected links between vaccines and autism, according to Scott. Other studies cited that cast doubt on vaccine safety are not well conducted, he added.
Declining Vaccination Rates Raise Disease Outbreak Fears
The rate of routine childhood vaccinations has dropped in the United States. This has allowed preventable diseases, including measles and whooping cough, to surge. In a call with state health officials, CDC disease detectives suggested that the US status as a country that has eliminated continuous measles spread is in jeopardy.
Dr Peter Hotez, director of the Centre for Vaccine Development at Texas Children’s Hospital, called the updated information “pure garbage.” He considers it a piece of dangerous health disinformation that needs immediate removal. Hotez wrote a book called “Vaccines Did Not Cause Rachel’s Autism” about his daughter’s diagnosis.
HHS spokesperson Andrew Nixon said the agency is updating the CDC’s website to reflect gold standard, evidence-based science. However, the new language contradicts another CDC page for parents. That page states, “scientific studies and reviews continue to show no relationship between vaccines and autism.”
Former CDC Officials Blindsided by Autism Vaccine Guidance 2025
Dr Demetre Daskalakis recently resigned as director of the CDC’s National Centre on Immunisation and Respiratory Diseases. He said on social media that the changes are “a national embarrassment.” The weaponisation of the CDC’s voice is getting worse, he wrote.
Daskalakis told CNN that the agency’s scientists were completely blindsided by the page update. This distortion of science under the CDC moniker is the reason he resigned with colleagues. One former CDC official who asked not to be named said, “This is the day CDC died.”
Figure 4: CDC leadership and health officials
Rather than restoring trust in America’s health agencies, moves like this have undermined it. Dr O’Leary fears the CDC vaccine guidance controversy will lead to fewer children being vaccinated. Children will suffer from diseases they did not need to suffer from, he warned.
What the CDC Vaccine Autism Update Means for Parents
The Department of Health and Human Services has launched a comprehensive assessment of the causes of autism. This includes investigations on plausible biologic mechanisms and potential causal links. However, experts say this represents a waste of valuable research money.
The Trump administration has hired longtime anti-vaccine allies to undertake new evaluations of government data. This includes David Geier, a discredited researcher once disciplined by the Maryland State Board of Physicians for practising medicine without a licence. The goal is to prove conspiracy theories that vaccine hazards have been hidden from the public.
Frequently Asked Questions
Q1: What did the CDC change on its website regarding vaccines and autism?
The CDC revised its webpage on 19 November 2025 to state that claiming vaccines do not cause autism is “not an evidence-based claim.” This reverses decades of messaging that clearly stated no link exists between vaccines and autism.
Q2: What does scientific research actually show about vaccines and autism?
Over 40 studies involving more than 5.6 million people consistently find no link between vaccines and autism. The 2019 Danish study of 650,000 children and the 2025 study of 1.2 million children both found no association.
Q3: Why are medical experts criticising the CDC vaccine autism update?
Experts accuse the CDC of cherry-picking data and misrepresenting research that proves vaccine safety. The Autism Science Foundation called the changes “anti-vaccine rhetoric and outright lies” that undermine public health.
Q4: How might this CDC vaccine guidance controversy affect public health?
Medical experts warn the update will reduce childhood vaccination rates and cause outbreaks of preventable diseases. The US status as a country that has eliminated continuous measles spread is now in jeopardy.
