National Institutes of Health Director Jay Bhattacharya told senators Tuesday that he has "not seen a study that suggests any single vaccine causes autism."
Bhattacharya made the remarks during testimony before the Senate Health, Education, Labor, and Pensions Committee, pushing back on claims that vaccines are linked to autism while emphasizing the need for serious scientific research into the condition's true causes.
His comments initially came in response to questioning from Sen. Bernie Sanders, I-Vt., who pressed Bhattacharya to clarify his views amid public debate and longstanding skepticism from Health and Human Services Secretary Robert F. Kennedy Jr., who has questioned vaccine safety in the past.
"I have not seen a study that suggests any single vaccine causes autism," Bhattacharya said, after Sanders repeatedly pressed him to answer plainly.
Bhattacharya said he is "absolutely convinced" that vaccinating children against measles is essential to addressing outbreaks and noted that extensive research has shown no link between the measles, mumps, and rubella (MMR) vaccine and autism.
He added that while some vaccines have been studied more extensively than others, broad claims blaming vaccines as a category are not supported by the evidence.
"When you're studying anything like this, you can't just say 'vaccines,'" Bhattacharya said. "You have to say vaccine by vaccine."
According to The Hill, Bhattacharya's testimony marked a notable contrast with Kennedy, who has argued that the science is not settled and has pointed to thimerosal, a mercury-containing preservative once used in some vaccines, as a possible factor.
Most childhood vaccines no longer contain thimerosal, and federal advisory panels have largely moved away from its use.
Sen. Maggie Hassan, D-N.H., cited dozens of studies involving more than one million children that found no connection between vaccines and autism, warning that revisiting debunked theories undermines public health and distracts from real answers.
Bhattacharya agreed that autism research should move forward rather than revisit settled questions.
He said the NIH is expanding efforts to study genetic, environmental, and developmental factors that may explain the sharp rise in autism diagnoses over recent decades.
"We don't know what causes autism," Bhattacharya said. "The NIH is committed to getting an answer for millions of families."
Sen. Jim Banks, R-Ind., noted that autism diagnoses have increased dramatically, from rare cases decades ago to roughly one in 31 children today.
Bhattacharya confirmed the increase and said the current administration is investing more resources than ever to understand why.
"This doesn't seem like a Republican or Democrat issue," Banks said, thanking Bhattacharya for prioritizing research that could help affected families.
Bhattacharya also addressed broader public mistrust in health institutions, noting that declining trust in doctors predates the current administration.
He said rebuilding confidence requires transparency, rigorous science, and focusing on evidence rather than political narratives.
Bhattacharya's testimony underscored a dual message: Vaccines remain a critical public health tool, while the federal government must do more honest, serious work to uncover what is driving the autism surge without silencing questions or chasing disproven theories.
Bhattacharya said NIH research will continue until families get real answers.
Charlie McCarthy ✉
Charlie McCarthy, a writer/editor at Newsmax, has nearly 40 years of experience covering news, sports, and politics.
© 2026 Newsmax. All rights reserved.