After a year of major shifts in the federal government’s policy toward vaccines, Americans are now more likely to trust the American Medical Association than the Centers for Disease Control and Prevention when the two conflict on vaccine guidance, a new survey shows.

The survey, conducted by the University of Pennsylvania’s Annenberg Public Policy Center, is one of several released in December that assess how the public is navigating a chaotic year of public health policy under President Donald Trump’s administration.

Trump’s Secretary of Health and Human Services, Robert F. Kennedy, Jr., is a longtime anti-vaccine activist. Earlier in 2025, he fired a committee of outside experts who advise the CDC on vaccine policy, replacing the committee with a handpicked group that includes other vaccine critics.

Soon after, the White House fired CDC director Susan Monarez in part because she had refused to unquestioningly sign off on the new committee’s recommendations.

The reconstituted panel subsequently changed recommendations on who should receive COVID-19 vaccines, prompting states like Pennsylvania to change their own policies around vaccine distribution to ensure continued access. The panel also recommended delaying hepatitis B shots for newborns, prompting outrage from medical experts who said the move will increase cases of the serious liver disease.

And in November, the CDC website, which for years had noted that decades of research show no link between receiving vaccines and developing autism, was updated to state the opposite. The site now reads: “The claim ‘vaccines do not cause autism’ is not an evidence-based claim because studies have not ruled out the possibility that infant vaccines cause autism.”

The move was decried by public health experts.

In the wake of those decisions, it’s crucial for medical providers and health communicators to understand how the public views vaccination, said Kathleen Hall Jamieson, Annenberg’s director.

Kennedy’s guidance often encourages patients to make their own decisions with doctors about vaccines, she said. But that often puts the burden on Americans to process scientific research on their own — and makes them vulnerable to misinformation, she said.

“The public doesn’t have time to do research on its own, on average, and in the process, they can get lost in a mire of misinformation and confusion very easily. It requires a skillset to navigate scholarly literature. And it’s easy to think one is doing one’s research when one is way down the rabbit hole,” Jamieson said.

Autism, vaccines, and trust in the CDC

Annenberg researchers wanted to understand where the public is turning for information on vaccines as trust in the CDC has fallen.

Shortly after the CDC changed its website on vaccines and autism, Annenberg researchers asked 1,006 adults about what they would do if the CDC’s advice conflicted with that of a major medical professional organization like the AMA, which strongly condemned the website changes.

While about half of the respondents said they believe the CDC provides trustworthy information on vaccine safety, the survey found that 35% of respondents said they would be more likely to accept recommendations from the AMA if they conflicted with the CDC. Just 16% of respondents said they would side with the CDC in that case.

That preference held true across political parties, and was particularly pronounced among older Americans. The only age group more likely to accept the CDC over the AMA were 18- to 29- year olds: 24% said they would accept the CDC’s recommendations, and 19% said they would accept the AMA’s.

“The fact that, as the CDC began to change statements, the public shifted its trust to other organizations on consequential issues — that’s a statement that says the public intelligence is real,” Jamieson said.

“The public is paying enough attention to say, ‘I can’t necessarily go to the CDC on that topic.’ That’s a statement that says we’re in better shape than you might have guessed that we were.”

Gauging public knowledge on vaccines

In another series of surveys, Annenberg researchers gauged what Americans already know about common vaccines in order to help public health officials communicate with the public more effectively.

“One of the goals of our surveying is to find what kinds of knowledge the public finds helpful and increase the likelihood that people make science-consistent decisions,” Jamieson said.

A survey on whooping cough, also known as pertussis, was conducted in the fall in response to a national rise in cases. The disease is caused by a bacterial infection and can result in a severe cough that lasts for months. It’s particularly dangerous for infants, especially those too young to be vaccinated against the disease.

About 30% of 1,637 respondents said they were not sure whether pertussis was the same as whooping cough and 35% said they were not sure whether a vaccine exists for it. Annenberg had reported similar findings a year before — an alarming conclusion, researchers said, because health officials have blamed a rise in cases in part on decreasing vaccination rates.

“Maybe we’re not doing the best possible job in communicating what we know about relative risks of the disease, the relative risks of vaccine, and the ways in which whooping cough is transmitted,” Jamieson said. “These are all questions designed to figure out the equation people are working through.”

Support for measles, mumps and rubella vaccines

Likewise, a late fall survey on attitudes toward the measles, mumps, and rubella vaccine (MMR) found that 86% of respondents say they’d be likely to recommend that eligible people in their household get the MMR vaccine.

That’s a “small but significant” decline from last year, when 90% said they would recommend the vaccine, researchers said.

Respondents are now also less likely to recommend vaccines for HPV and polio.

That may be because the MMR vaccine has been so effective that the public can no longer remember what it was like to contract measles, Jamieson said.

“I am elderly. I have gone through whole periods of my life in which these vaccines did not exist. I know what measles looks like — extraordinarily uncomfortable — with risks that are real and demonstrable,” Jamieson said. “And the vaccine has worked for people I care about in the subsequent generations.”

Support for MMR vaccines are still overwhelmingly high, Jamieson said. But the threshold to maintain herd immunity for measles is also high — about 95% of people must be vaccinated in order to prevent the spread of the disease and protect people who cannot be vaccinated.

And, if people live in communities where vaccines are less accepted, they could be at higher risk than the general population.

“The state of Pennsylvania can be at 95%, but if my church isn’t at 95%, I can get measles if I’ve not been fully immunized or if I can’t be vaccinated,” Jamieson said.

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