By Sabrina Siddiqui and Jennifer Calfas

The former director of the Centers for Disease Control and Prevention rebutted Health and Human Services Secretary Robert F. Kennedy Jr. characterization of her dismissal, telling a Senate committee Wednesday she was fired after she refused to compromise her scientific integrity.

Former CDC director Susan Monarez and Dr. Debra Houry, the CDC's chief medical officer who recently resigned, are testifying in front of a Senate health committee to examine the recent turmoil at the federal health agency and its effects on children's health. The testimony comes two weeks after Republicans and Democrats questioned Kennedy in a contentious hearing about his dismissal of experts on a key immunization panel as well as Monarez's firing.

Here are several key takeaways from the hearing so far.

Monarez details her dismissal

Monarez described her interactions with Kennedy that led to her firing less than a month into the job. In her opening statement, Monarez said that days before her dismissal, Kennedy's office told her she must receive their approval before making personnel and policy decisions.

She said Kennedy said the childhood vaccine schedule would be changing starting in September, that he had discussed changing the schedule with the president, and that "I needed to be on board with it." The childhood vaccine schedule is a set of recommendations from the CDC about when children should get vaccines and which ones they should receive.

She said Kennedy also suggested she meet with Aaron Siri, an attorney who has worked with anit-vaccine groups and has petitioned the Food and Drug Administration to remove a commonly used polio vaccine from the market.

Monarez said that Kennedy in late August had instructed her to agree to approve all future recommendations from a vaccine advisory panel filled with his appointees, and to fire CDC vaccine policy officials. Monarez said Kennedy told her to resign if she wasn't willing to do so. She said she told him she couldn't agree to approve future recommendations without reviewing evidence and couldn't fire experts with no basis.

"He told me he had already spoken with the White House several times about having me removed," Monarez said in her remarks.

Those two demands "were inconsistent with my oath of office and the ethics required of a public official," according to her prepared remarks. "Even under pressure, I could not replace evidence with ideology or compromise my integrity," Monarez said.

At a hearing earlier this month, Kennedy called Monarez a liar and denied her characterization of these events, which had been detailed in the media and referenced in an opinion piece she wrote in The Wall Street Journal.

Senators question firing

Louisiana Sen. Bill Cassidy, the Republican who chairs the Senate health committee and who invited Monarez to testify, kicked off the hearing by questioning whether the Senate had made a mistake when it confirmed her less than two months ago, and whether Kennedy and others had been incorrect to laud her at the time as qualified and accomplished.

"Turmoil at the top of the nation's top public health agency is not good for the health of the American people," said Cassidy, a physician who was also among Kennedy's sharpest Republican critics when the health secretary testified before a separate Senate committee earlier this month.

Sen. Bernie Sanders (I., Vt.), the committee's ranking member, questioned how Monarez went from being touted by the Trump administration as a public health expert "with unimpeachable scientific credentials" to being called "a liar" in less than a month.

"It's quite a transformation," Sanders said. "Dr. Monarez was fired because she refused to act as a rubber stamp to implement Secretary Kennedy's dangerous agenda to substantially limit the use of safe and effective vaccines."

Former CDC official warns of censorship

Houry, the CDC's top career scientist, who resigned shortly after Monarez's dismissal, said Kennedy has censored science and politicized the agency.

"I resigned because CDC leaders were reduced to rubber stamps, supporting policies not based in science and putting American lives at risk," Houry said. "I could not, in good conscience, remain under those conditions."

Under Kennedy's leadership, flu campaigns were halted and CDC staff learned of the CDC's changes to Covid-19 vaccine guidelines in May from Kennedy's post on X, Houry said. The agency's experts haven't seen a justification for this change, Houry said.

"Due to the secretary's actions, our nation is on track to see drastic increases in preventable diseases and declines in health," Houry said. "Trust and transparency has been broken."

Write to Sabrina Siddiqui at sabrina.siddiqui@wsj.com and Jennifer Calfas at jennifer.calfas@wsj.com

(END) Dow Jones Newswires

September 17, 2025 11:10 ET (15:10 GMT)

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