Cdc say vaccine cause autism
Executive summary
The Centers for Disease Control and Prevention changed a webpage on Nov. 19–20, 2025 to remove language that “vaccines do not cause autism” and to say instead that that claim “is not an evidence‑based claim because studies have not ruled out the possibility that infant vaccines cause autism,” prompting widespread rebukes from medical groups and scientists [1] [2]. Major news outlets, medical societies and public‑health experts characterize the update as a break with decades of consensus that found no causal link between vaccines and autism and say the change was driven by political appointees under HHS Secretary Robert F. Kennedy Jr. [3] [4] [5].
1. What exactly changed on the CDC website — and who ordered it?
The CDC’s “Autism and Vaccines” page was rewritten in mid‑November 2025 to replace an earlier statement that “vaccines do not cause autism” with text saying that that claim “is not an evidence‑based claim” and asserting that studies have not ruled out a possible contribution of infant vaccines to autism; the update also said some studies supporting a link were “ignored” by authorities [1] [6]. Multiple outlets report that political appointees inside the Department of Health and Human Services — and HHS Secretary Robert F. Kennedy Jr. personally — directed or approved the change, while career CDC scientists were sidelined [7] [4] [2].
2. How do public‑health organizations and scientists react?
Professional bodies and many scientists condemned the rewrite. The Infectious Diseases Society of America and the American Medical Association publicly stated that decades of rigorous research show vaccines do not cause autism and called the CDC language change reckless and harmful [8] [9]. Reporting in outlets such as The Washington Post and STAT quotes career scientists and autism advocates who say the agency’s credibility has been undermined [3] [10].
3. What is the scientific evidence that existed before this change?
Longstanding, large‑scale studies and reviews have repeatedly found no causal link between vaccines (including MMR and vaccine ingredients like aluminum or thimerosal formulations) and autism; for example, large population studies from Denmark and comprehensive reviews over decades were cited as evidence against a connection [11] [2]. News organizations and experts note that studies claiming links were found to be poorly done, non‑replicable or fraudulent, most famously the retracted 1998 Wakefield paper [12] [13].
4. What arguments do proponents of the change advance?
HHS under Secretary Kennedy framed the update as an effort to acknowledge uncertainties and “gaps” in vaccine‑safety science and to launch a broader assessment of autism causes; the updated CDC text explicitly calls for a comprehensive assessment and invokes the Data Quality Act as part of the rationale for revising language [1] [5]. Supporters argue agencies should be transparent about limitations of any single statement like “vaccines do not cause autism” because science rarely permits absolute negatives [12].
5. What are critics’ counterarguments and concerns about impact?
Critics say the rewrite misuses a logical quirk — that inability to “prove never” is not evidence of a positive link — and that the CDC is lending credibility to a debunked claim, thereby fueling vaccine hesitancy and risking resurgence of preventable diseases [4] [8]. Reporting notes immediate worries about declining vaccination rates, growing outbreaks (cited measles surge), and the political context of placing longtime vaccine skeptics in leadership roles [13] [5].
6. What remains uncertain or missing from current reporting?
Available sources document the webpage text change, political involvement, and the reaction from medical communities, but they do not provide published evidence overturning the large prior epidemiologic studies that found no vaccine‑autism causal link; major recent studies showing no association (for instance, a 2025 Danish study on aluminum exposure) are cited as still supporting no link, and sources say studies claiming links have been discredited [12] [11]. Detailed internal CDC deliberations, the full list of studies HHS intends to review, and what new research will be funded or how it will be conducted are not described in the current reporting [1] [2].
7. Takeaway for readers deciding what to believe and do
As of these reports, the official CDC webpage language has shifted and triggered bipartisan alarm in the scientific and medical communities; however, many established scientific reviews and large population studies continue to find no causal link between vaccines and autism, and leading medical societies have reaffirmed that conclusion [9] [11]. Readers should note the political context reported by Reuters, The New York Times and others and watch for formal, peer‑reviewed new studies or agency technical reports before treating the website change as new scientific evidence [4] [2].
If you want, I can compile and summarize the key studies and reviews cited by reporters and professional societies that previously supported the conclusion “vaccines do not cause autism,” or track new HHS/CDC publications as they appear.