During his Senate confirmation hearings, Health Secretary Robert F. Kennedy Jr. suggested he wouldn’t undermine vaccines.

“I am not going to go into HHS and impose my preordained opinions on anybody at HHS,” he said. “I’m going to empower the scientists at HHS to do their job and make sure that we have good science that is evidence based.”

He also said he wouldn’t halt congressionally mandated funding for vaccination programs, nor impose conditions that would force local, state or global entities to limit access to vaccines or vaccine promotion.

“I’m not going to substitute my judgment for science,” he said.

Yet the Department of Health and Human Services under Kennedy has taken unprecedented steps to change how vaccines are evaluated, approved and recommended — sometimes in ways that run counter to established scientific consensus.

Here’s a look at what Kennedy has said and done since becoming the nation’s top health official Feb. 13.

Childhood vaccine schedule

Sen. Bill Cassidy, a physician who was unsettled about Kennedy’s antivaccine work, said Kennedy pledged to him that he wouldn’t change existing vaccine recommendations.

“I recommend that children follow the CDC schedule. And I will support the CDC schedule when I get in there,” Kennedy said at his Senate confirmation hearing.

Kennedy also said he thought the polio vaccine was safe and effective and that he wouldn’t seek to reduce its availability.

Feb. 18: Kennedy vows to investigate the childhood vaccine schedule that prevents measles, polio and other dangerous diseases.

Early March: The National Institutes of Health cancels studies about ways to improve vaccine trust and access.

April 9: Kennedy tells CBS News that “people should get the measles vaccine, but the government should not be mandating those,” before then continuing to raise safety concerns about vaccines.

May 22: Kennedy issues a report that, among other things, questioned the necessity of mandates that require children to get vaccinated for school admission and suggested that vaccines should undergo more clinical trials, including with placebos. The report has to be reissued later because the initial version cited studies that don’t exist.

May 30: The Centers for Disease Control and Prevention removes COVID-19 vaccination guidance for pregnant women and says healthy children “may” get the shots.

June 25: A group of vaccine advisers picked by Kennedy announce they are establishing a work group to evaluate the “cumulative effect” of the children’s vaccine schedule.