Susan Monarez, President Donald Trump’s nominee to be the director of the Centers for Disease Control and Prevention, testifies during her confirmation hearing before the Senate Committee on Health, Education, Labor, and Pensions in the Dirksen Senate Office Building on June 25, 2025 in Washington, D.C. (Photo by Kayla Bartkowski/Getty Images)

WASHINGTON — President Donald Trump’s candidate to lead the Centers for Disease Control and Prevention advanced out of a Senate committee Wednesday following a party-line vote, moving her one step closer to confirmation.

Susan Monarez’s nomination now goes to the floor, where she will likely secure the backing needed to officially take on the role of CDC director after garnering support from Republicans across the political spectrum during the committee’s 12-11 vote.

Senate Majority Leader John Thune, R-S.D., will be in charge of scheduling that vote, though if it isn’t held during the next few weeks, Monarez will have to wait until after the chamber’s August recess.

Chairman Bill Cassidy, R-La., said during the Health, Education, Labor and Pensions Committee’s markup he believes Monarez is a strong candidate for CDC director and that he hopes she will help get the nation’s ongoing measles outbreak under control.

“The United States needs a CDC director who makes decisions rooted in science, a leader who will reform the agency and work to restore public trust in health institutions,” Cassidy said. “With decades of proven experience as a public health official, Dr. Monarez is ready to take on this challenge.”

Sanders criticizes Monarez on vaccine safety

Every Republican senator on the committee, including Maine’s Susan Collins and Alaska’s Lisa Murkowski, voted to advance Monarez’s nomination.

Vermont independent Sen. Bernie Sanders, ranking member on the panel, opposed Monarez’s advancement along with the Democrats on the committee.

Sanders argued that during Monarez’s time as acting director of the CDC, she didn’t do enough to counter Secretary of Health and Human Services Robert F. Kennedy Jr., especially on the safety of vaccines. 

“Today, the United States is reporting the highest number of measles cases in 33 years,” Sanders said. “In my view, we need a CDC director who will defend science, protect public health and repudiate Secretary Kennedy’s dangerous conspiracy theories about safe and effective vaccines that have saved, over the years, millions of lives.”

Second CDC choice from Trump

Monarez testified before the Health, Education, Labor and Pensions Committee in June, a standard part of the confirmation process.

Trump originally selected former Florida U.S. Rep. Dave Weldon to run the Atlanta-based CDC shortly after he secured election to the Oval Office in November. But the White House pulled Weldon’s nomination in March, after it appeared he couldn’t secure the votes needed for confirmation.

Later that month, Trump announced his plans to nominate Monarez in a social media post.

“Dr. Monarez brings decades of experience championing Innovation, Transparency, and strong Public Health Systems,” Trump wrote. “She has a Ph.D. from the University of Wisconsin, and PostDoctoral training in Microbiology and Immunology at Stanford University School of Medicine.

“As an incredible mother and dedicated public servant, Dr. Monarez understands the importance of protecting our children, our communities, and our future. Americans have lost confidence in the CDC due to political bias and disastrous mismanagement. Dr. Monarez will work closely with our GREAT Secretary of Health and Human Services, Robert Kennedy Jr. Together, they will prioritize Accountability, High Standards, and Disease Prevention to finally address the Chronic Disease Epidemic and, MAKE AMERICA HEALTHY AGAIN!”

Susan Monarez, President Donald Trump’s nominee to be the director of the Centers for Disease Control and Prevention, testifies during her confirmation hearing before the U.S. Senate Committee on Health, Education, Labor, and Pensions on June 25, 2025. (Photo by Kayla Bartkowski/Getty Images)

WASHINGTON — Members of the U.S. Senate Committee on Health, Education, Labor and Pensions pressed President Donald Trump’s nominee to lead the Centers for Disease Control and Prevention about vaccine recommendations Wednesday after the Health and Human Services secretary fired members of a critical vaccine panel this month.

Trump’s pick, former acting CDC Director Susan Monarez, said that she trusted vaccines while defending HHS Secretary Robert F. Kennedy Jr.’s decision this month — widely seen as part of a vaccine-skeptical agenda — to fire all 17 members of the Advisory Committee on Immunization Practices, or ACIP, and recommend eight new members.

“Part of the secretary’s vision in restoring public trust is making sure that the American people can be confident in the way the evidence and science is driving decision-making,” she told senators.

The panel’s seven members — one dropped out this week — will meet Wednesday and Thursday to review data and vote on new vaccine recommendations. The recommendations carry significant weight as insurance providers and federal health programs like Medicaid use them to determine if shots are covered and schools rely on them for immunization mandates.

Cassidy questions

Louisiana Sen. Bill Cassidy, who chairs the committee, said he was concerned about ACIP, especially as a non-CDC staff member is scheduled to give a presentation to the committee about thimerosal, a mercury-based preservative. The panel is expected to vote on approving flu shots that contain the compound.

Lyn Redwood, the former head of Children’s Health Defense, the anti-vaccine group that Kennedy founded, is giving the presentation arguing that thimerosal causes autism. The CDC’s own research shows that thimerosal does not cause autism. 

Cassidy said that while Monarez had no part in this week’s ACIP meeting, or the agenda, he said that “if the ACIP hearing today is being used to sow distrust, I would ask that going forward, that you would make sure that there really was a balanced perspective.”

“Yes, someone can speak as a critic, but there should be someone who is reviewing the overwhelming evidence of the safety of vaccines,” Cassidy, who is a physician, said.

Monarez, who was the agency’s acting director from January to March, said that she trusted vaccines and that immunization was important to save lives.

If Monarez is confirmed by the Senate, she would be the first director of the CDC without a medical degree in nearly 70 years. She has a Ph.D. in microbiology and immunology.

More concerns about vaccine panel

Cassidy was not the only Republican on the panel concerned about the firing of all the members of ACIP.

Alaska Republican Sen. Lisa Murkowski said she was concerned about the backgrounds of the seven new panelists.

“I would hope that one of the things that you would all be looking into is to make sure that these individuals are going to be looking at the science in front of them, (and) leave their political bias at home,” Murkowski said.

Democratic Sens. Patty Murray of Washington state and Angela Alsobrooks of Maryland also pressed Monarez about Kennedy’s actions to fire everyone on the panel.

Murray asked Monarez if the new members of the panel voted to not recommend vaccines, if she would listen to that recommendation.

Monarez sidestepped the question and said the roles at ACIP were difficult to fill and that members needed to pass an ethics process.

“If they have not gone through an ethics approval process they shouldn’t be participating in the meetings,” she said.

Alsobrooks asked Monarez if she believed the 17 members fired from ACIP lacked qualifications.

Monarez did not answer the question, but said Kennedy’s reasoning for “resetting the ACIP to a new cohort was going to be on the path of restoring public trust.”

Grant funding and layoffs

Senators also raised concerns about grants that had been canceled, even though Congress already approved the funds.

Maine GOP Sen. Susan Collins, who is the chairwoman of the Senate Committee on Appropriations, said that her state is suffering from a high level of Lyme disease and as a result a vaccine was in the works at a research institute in Maine.

“This vaccine is very promising and I want to make sure that it is allowed to continue to its conclusion,” Collins said.

Monarez agreed and said if she is confirmed, she will specifically work to make sure funding for that vaccine continues.

“It’s ironic that our dogs can get a vaccine to protect them against tick-borne illnesses like Lyme disease but we humans can’t and I hope we can remedy that,” Collins said.

Sen. Tim Kaine, Democrat of Virginia, pressed Monarez about the elimination of the Office on Smoking and Health at the CDC. He asked if she was involved in laying off all the staff in April, the month after her brief stint as acting director ended.

“I had no participation in (the layoffs) after I left,” she said.

Fluoride in water

Alsobrooks pressed Monarez about Kennedy’s push to have the CDC stop recommending that low levels of fluoride be placed in public drinking water.

Fluoride is added in drinking water to help prevent cavities, tooth decay and other dental health issues.

Alsobrooks asked Monarez, who is her constituent, if the public water supply that contains fluoride in Potomac, Maryland, where Monarez lives, was safe to drink.

“I believe the water in Potomac, Maryland, is safe,” Monarez said.