Sen. Bill Cassidy of Louisiana is criticizing the Centers for Disease Control and Prevention over a website dealing with autism and vaccines, opening a new dispute over how the federal agency communicates on one of the most sensitive topics in public health.

Cassidy, a Republican who has repeatedly challenged President Donald Trump’s administration on health matters, said the CDC’s handling of the page was deeply problematic. His criticism adds political pressure to a debate that often sits at the intersection of science, public trust and government messaging.

The issue centers on the content presented on the CDC website about autism and vaccines. While the full details of the page were not included in the available report, Cassidy’s response suggests he viewed the agency’s approach as inappropriate and potentially harmful in how it addressed the subject.

The clash highlights how vaccine-related communication from federal health agencies can quickly become a flashpoint, especially when autism is involved. It also underscores Cassidy’s willingness to break with his own party’s leadership and challenge federal health officials when he believes their public messaging misses the mark.