WASHINGTON (AP) — The Trump administration is canceling studies about ways to improve vaccine trust and access, a move that comes in the midst of a large measles outbreak fueled by unvaccinated children.

Researchers with grants from the National Institutes of Health to study why some people have questions or fears about vaccines and how to help those who want to be vaccinated overcome barriers are getting letters canceling their projects.

The step — first reported by The Washington Post, which cited dozens of expected cancellations — is highly unusual, as entire swaths of research typically aren’t ended mid-stream.

“It is the policy of NIH not to prioritize research activities that focuses gaining scientific knowledge on why individuals are hesitant to be vaccinated and/or explore ways to improve vaccine interest and commitment,” say NIH letters sent to two researchers with different grants.

“It’s really concerning,” said Dr. Sean O’Leary of the American Academy of Pediatrics, who viewed and read aloud from two letters other scientists had received, noting the claim that the research doesn’t benefit people or improve quality of life.

“That’s inaccurate. Vaccines clearly save lives, there’s no question about the science of that,” O’Leary said. Better understanding what parents want to learn from their pediatrician — or adults’ questions about their own shots — is “really about improving care and not just necessarily about just the vaccination rates.”

“You can’t say you’re for vaccine safety and not study how people think about vaccines,” added Dr. Georges Benjamin of the American Public Health Association.