WASHINGTON — Sen. Bernie Sanders is demanding that Senate Health Committee Chairman Bill Cassidy hold a hearing to set the record straight that there is no link between vaccines and autism.
Cassidy, R-La., a doctor, has been outspoken about his belief that vaccines are “safe and effective and will not cause autism.”
But in a letter shared exclusively with NBC News, Sanders, I-Vt., said Cassidy must counter statements by Health and Human Services Secretary Robert F. Kennedy Jr., who has undermined public faith in vaccines and raised questions about their connection to autism. Cassidy’s was the deciding vote to confirm Kennedy.

“The reality is that since Secretary Kennedy has been in office, he has continued his longstanding crusade against vaccines and his advocacy of conspiracy theories that vaccines cause autism — all of which have been repeatedly rejected by scientists,” Sanders wrote.
Sanders is Cassidy’s counterpart as the ranking member on the powerful Health, Education, Labor, and Pensions Committee.
Sanders pointed to Kennedy’s firing all 17 members of a key federal vaccine advisory panel and replacing them with members of his own choosing, including several appointees who promoted a link between vaccines and autism.
Kennedy separately directed the Centers for Disease Control and Prevention to change a webpage that once said vaccines do not cause autism to suggest, without evidence, that health authorities “ignored” possible links between the shots and autism. The CDC kept the statement “Vaccines do not cause Autism” on the webpage but added an explicit dig at Cassidy with an asterisk saying it was only there because of a promise made to the Health Committee chairman.

Kennedy has also asserted that there was a link between Tylenol and autism and teamed up with President Donald Trump to encourage pregnant women to avoid the pain reliever. Tylenol orders for some pregnant women fell after Trump’s warning, though a January analysis of research found no link between use of the drug in pregnancy and autism or other neurodevelopmental disorders.
Pediatricians and vaccine experts have long said no credible research has ever suggested a link between autism and vaccines.
Sanders called on Cassidy to hold a hearing with “leading scientists, physicians, and public health experts” to “review the existing body of research on autism, discuss how federal agencies evaluate scientific evidence, and clarify what is known.”
Cassidy did not respond to a request for comment on the letter.
Cassidy faces a tough re-election campaign in November. He has a primary challenge from Trump-endorsed Rep. Julia Letlow, R-La., who has the backing of Make America Healthy Again PAC, run by Kennedy ally Tony Lyons.
Cassidy invited Kennedy to testify before the Health Committee on Sept. 18 for an oversight hearing, but, six months later, that hearing has not happened. Since that invitation, Cassidy has repeatedly told NBC News that a date for the hearing is being “worked out.”
