Most Americans Reject Vaccine-Autism Link, New Poll Finds, as Confusion Persists Over RFK Jr.'s Measles Stance

PHILADELPHIA — Most Americans do not believe childhood vaccines cause autism, according to a new national survey, though the share rejecting the debunked claim remains lower than it was five years ago and many people are unsure where Health and Human Services Secretary Robert F. Kennedy Jr. stands on measles vaccination.

About 68% of U.S. adults surveyed by the University of Pennsylvania's Annenberg Public Policy Center said it is false that "vaccines given to children for diseases like measles, mumps, and rubella cause autism." Thirteen percent said the statement was true, and 19% said they were not sure.

Those figures are statistically unchanged since 2022. But in June 2021, a significantly larger share, 74%, said it was false to claim a link between vaccines and autism.

The survey was conducted Aug. 4-17 among 1,904 U.S. adults and has a margin of sampling error of plus or minus 3.2 percentage points.

Small shift on autism beliefs

The poll found modest movement on a related question. Just over half of respondents, 52%, said fully vaccinated children are "about as likely" to show signs of autism as children who are not fully vaccinated. Nine percent said vaccinated children are "more likely" to show signs of autism, down from 12% in February. Twelve percent said they are "less likely," and 28% were unsure.

"This small decrease in endorsing a link between vaccination and autism is good news in our survey data," said Ken Winneg, the policy center's managing director of survey research.

Winneg cautioned, however, that when researchers tracked the same people over time, they found no relationship between people learning Kennedy's position on measles vaccination and a decline in belief in the false autism link.

Decades of scientific research, including large studies involving millions of children, have found no link between vaccines and autism.

Public sides with pediatricians over CDC

The survey also asked about a controversial change made last year to the Centers for Disease Control and Prevention's website.

On Nov. 19, 2025, the CDC revised its "Autism and Vaccines" page. The page previously said studies have shown no link between receiving vaccines and developing autism spectrum disorder. The revised language states that the claim "vaccines do not cause autism" is not evidence-based because studies have not ruled out the possibility that infant vaccines cause autism.

When asked which statement was closer to their own view, 55% of respondents chose the American Academy of Pediatrics' position that studies have repeatedly found no credible link between childhood vaccines and autism. Only 18% chose the CDC's revised language, while 27% were unsure.

Annenberg researchers have previously found that holding false beliefs about vaccines, including that the MMR vaccine causes autism, is linked to a lower likelihood of recommending the MMR vaccine and reluctance to take or recommend other vaccines.

Confusion over Kennedy's position

The poll comes as measles cases in the United States have climbed to their highest levels in decades, a rise attributed to declining vaccination rates.

Kennedy, a longtime vaccine skeptic, told American parents on Aug. 2 that they should get their children vaccinated against measles. But the survey found the public evenly split on his position.

Thirty-one percent of respondents said Kennedy recommends that children be vaccinated against measles, up significantly from 23% in August 2025. But 29% said he does not recommend the vaccine, and 40% said they were unsure.

As HHS secretary, Kennedy has made misleading and unsupported claims about the MMR vaccine, measles and vaccination in general, according to FactCheck.org, a project of the Annenberg Public Policy Center. He has also been criticized for downplaying the risks of measles during the 2025 outbreak in Texas.

Kathleen Hall Jamieson, the policy center's director emerita, said the country is paying a price for vaccine skepticism.

"As measles cases rise and the U.S. is poised to lose its measles elimination status, this country is paying the price for skepticism about vaccination against measles that RFK Jr. played a central role in promoting," Jamieson said.

She added that Kennedy's ability to address the current outbreaks is hampered because most adults are either unsure about his position on childhood measles vaccination or believe he does not recommend it.

Measles threat grows

Measles is one of the most contagious diseases known. The virus spreads through the air and can cause serious complications, including pneumonia, brain swelling and death, particularly in young children.

The United States declared measles eliminated in 2000, meaning the disease was no longer continuously spreading within the country. That status is now at risk as outbreaks continue.

"Measles is highly contagious," said Laura A. Gibson, a research analyst at the policy center. "As we've seen this year, communities that don't maintain 95% vaccination rates are at risk for outbreaks."

Public health experts say a 95% vaccination rate is needed to maintain community protection, known as herd immunity. Vaccination rates among kindergartners have fallen below that threshold nationally in recent years, and exemptions from school vaccine requirements have risen.

Kennedy's favorability remains low

The survey also found Kennedy's public image has not improved. Fewer than 1 in 4 respondents, 23%, said they have a favorable view of him, unchanged from August 2025.

Half said they have an unfavorable opinion, including 42% who said their view was "very unfavorable," up from 37% a year earlier.

About the survey

The survey is part of the Annenberg Science and Public Health survey series, which has tracked Americans' knowledge, beliefs and behaviors on vaccination, COVID-19, flu, RSV and other health issues since April 2021.

It was conducted for the policy center by SSRS, an independent research company, by web and telephone among a nationally representative probability sample drawn from the SSRS Opinion Panel. Results were weighted to represent the U.S. adult population.

The findings suggest that while a solid majority of Americans reject the false claim that vaccines cause autism, a meaningful minority either believes it or remains uncertain. Public health officials say that uncertainty, combined with mixed messages from federal health leaders, could make it harder to reverse declining vaccination rates and contain measles outbreaks in the months ahead.