Susan Monarez, former director of the Centers for Disease Control and Prevention, testifies in front of the Senate Committee on Health, Education, Labor, and Pensions in Washington, D.C., on Sept. 17, 2025.
On Aug. 27, Monarez was fired from the CDC amid policy disagreements with Health and Human Services Secretary Robert F. Kennedy Jr.
Dr. Debra Houry speaks during a Senate committee hearing with former CDC Director Susan Monarez who was ousted after resisting changes to vaccine policy.

WASHINGTON – A top scientist who was pushed out of the Trump administration last month defended herself at a Sept. 17 congressional hearing, raising alarm about Health and Human Services Secretary Robert F. Kennedy Jr.'s leadership and the country's lack of preparedness for the next public health crisis.

In dramatic testimony, Susan Monarez told GOP and Democratic senators she was asked to compromise her integrity as head of the Centers for Disease Control and Prevention. She was fired on Aug. 25 after she said she refused to dismiss career officials who disagreed with Kennedy about the efficacy of vaccines.

She also said she was directed to give "blanket approval" preemptively for recommendations from a key CDC vaccine panel "regardless of the scientific evidence."

The alleged demands, Monarez said, were against her ethics as a scientist and public servant.

"I was fired for holding the line on scientific integrity," she said. "But that line does not disappear with me. It now runs through every parent deciding to vaccinate a child, every physician counseling new patients and every American who demands accountability."

The striking scene on Capitol Hill underlined a rare area of growing discontent among congressional Republicans with President Donald Trump and his administration. Though GOP senators initially supported RJK Jr. to become the nation's top health official, his penchant for vaccine skepticism – and the CDC turmoil that has ensued from that – have sparked frustration among lawmakers who are usually in lockstep with the White House.

"Turmoil at the top of the nation's public health agency is not good for the American people," said Sen. Bill Cassidy, a Republican doctor from Louisiana and the chair of the Senate's health committee.

Monarez's allegations "strike at the core of the CDC's credibility," he said.

The hearing was reminiscent of previous times ousted Trump administration officials have taken to whistleblowing on Capitol Hill, particularly at the outset of the Republican president's first term. In June 2017, former FBI Director James Comey told a Senate panel that Trump asked him for "loyalty" before firing him. Former acting Attorney General Sally Yates also told lawmakers that year she was pushed out for refusing to defend Trump's travel ban.

Monarez describes firing in vivid detail

Monarez said she had three heated meetings with RFK Jr. on Aug. 25.

In one of the meetings, she said he asked her to fire other CDC officials or hand in her resignation. He also told her to rubber stamp upcoming vaccine recommendations, she said.

She refused to step down, and "that is when he told me he had already spoken to the White House about having me removed," she said.

"The entire meeting was very tense," Monarez said. "He was very upset."

Testifying in front of a separate congressional committee two weeks ago, Kennedy said he did not ask Monarez to preapprove vaccine recommendations, but just wanted her to keep an open mind about them.

HHS spokesperson Andrew Nixon said in a statement: "Monarez was fired for declaring herself untrustworthy to the Secretary and acting maliciously to undermine the President’s agenda. This made it impossible for her to carry out the mission of HHS and the CDC with integrity and transparency."

Monarez says RFK Jr. told her not to talk to Congress

Monarez also said that Kennedy told her not to raise concerns about his leadership with members of Congress.

"I was instructed to not speak directly with senators," she said.

That suggestion enraged Democrats.

"Putting a gag order on a CDC director and directing her not to speak to those who have confirmed her, and to whom she is responsible for oversight, is a very serious matter," said Sen. Tim Kaine, D-Virginia.

Nixon said Monarez was "grossly distorting" expectations that HHS staff "follow standard, long-standing protocols for communicating with Congress through the office of the assistant secretary for legislation."

Questioning childhood vaccines schedule

Sen. Rand Paul, R-Kentucky, got into a testy exchange with Monarez about the CDC's childhood vaccine recommendations, as well as the efficacy of COVID-19 vaccines and hepatitis B shots for newborns.

"Does the COVID vaccine reduce the rate of death for children under 18?" asked Paul.

"It can," Monarez said.

"That's a ridiculous answer," he replied.

Paul said Monarez’s refusal to fire scientists was not about protecting "unbiased" and "beautiful scientists" but rather those who recommended that children six months and older could receive COVID vaccines.

Paul, an ophthalmologist, said he was in favor of changing the childhood vaccine schedule.

Kennedy received no briefings during measles outbreak, spread misinformation

In an exchange with Sen. Susan Collins, R-Maine, another public health official who resigned from the Trump administration said the CDC's response to the recent measles outbreak differed significantly from the way the agency usually operates.

Debra Houry, the CDC's former chief medical officer, said she never briefed Kennedy.

"The center director who saw measles never briefed the secretary and during an outbreak response, usually you would be briefing leadership," she said.

Kennedy also spread misinformation about vaccines and recommended drugs to physicians that would "result in harm," Houry said.

"He said things like vaccines have fetal parts, and I had to send a note to our leadership team to correct that misinformation," she said.

Kennedy has claimed that some religious groups avoid the measles, mumps and rubella (MMR) vaccine because it contains "aborted fetus debris" and "DNA particles."

In fact, vaccines are "produced using human cell lines that originated from two legal abortions in the 1960s but these cells are not present in the final vaccine," according to Columbia Law School’s Sabin Center.

This article originally appeared on USA TODAY: 'Not good for the American people': Turmoil on RFK Jr.'s turf prompts rare GOP pushback

Reporting by Zachary Schermele and Swapna Venugopal Ramaswamy, USA TODAY / USA TODAY

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