The Centers for Disease Control and Prevention quietly revised language on a vaccine safety web page to state that the claim 'vaccines do not cause autism' cannot be ruled as evidence‑based, a shift that echoed long‑discredited assertions and drew immediate backlash from major medical organizations. Critics warned the change undermines decades of epidemiologic research and threatens public confidence in routine childhood immunizations. Public health experts cited multiple large studies showing no causal link between vaccines and autism and flagged the edit as influenced by Health Secretary Robert F. Kennedy Jr.’s skepticism. Separate analyses report declining vaccine uptake since the change in HHS leadership, complicating outbreak prevention and routine pediatric care. The agency said it will undertake further assessments, but the controversy has already prompted industry groups and clinicians to call for rapid clarification and restoration of evidence‑based messaging to avoid widening vaccine hesitancy.