By Liz Essley Whyte, Jennifer Calfas and Sabrina Siddiqui

The Centers for Disease Control and Prevention entered a precarious new chapter as health secretary Robert F. Kennedy Jr. sketched a vision for radically remaking it while current and former employees of Kennedy's agency called on him to resign.

In op-eds and interviews this week, Kennedy said the CDC had squandered public trust and suggested further changes to its workforce were necessary. He said he wants to shift the agency to focus on infectious diseases, moving chronic disease work to his "Administration for a Healthy America."

Inside the CDC, employees are torn on the agency's future and their own. Some say they anticipate more resignations as Kennedy seeks to advance antivaccine policies at the federal level. Others say they are determined to stay, out of concern that a mass exodus would further strip the country's leading health agency of its institutional expertise.

On Wednesday, more than 1,000 current and former Health and Human Services employees called on Kennedy to resign in a letter to the secretary and members of Congress. The letter said the secretary's actions threaten the nation's health, citing his involvement in former CDC Director Susan Monarez's dismissal and his appointment of vaccine skeptics to the Advisory Committee on Immunization Practices, among other reasons.

Lawmakers have raised concerns about the turmoil. Kennedy will face scrutiny from the Senate Finance Committee during a hearing Thursday morning, as Republicans as well as Democrats this week have questioned the secretary's handling of the agency.

Kennedy told CDC employees in an email last week that he aims to "restore trust" to the agency with his changes. But employee morale has continued to decline after Monarez, who clashed with Kennedy on vaccine policy and other issues, was removed and other senior leaders resigned last week, current and former CDC employees said.

New acting director Jim O'Neill, a Kennedy aide and veteran of the first Trump administration, made an unannounced visit to the CDC's Atlanta headquarters this week to begin implementing Kennedy's vision.

Sen. Lisa Murkowski (R., Alaska) said she is concerned about the direction Kennedy has gone on vaccines and added that his actions haven't aligned with promises he made to her before she voted to confirm him.

"I don't have a problem at all focusing on infectious diseases, making sure that we've got more epidemiologists in there," Murkowski said. "We want to have this based on science. Right now, it just doesn't feel that way."

Senior leaders who resigned following Monarez's ouster took to the airwaves this week to defend the agency's work, even as Kennedy told reporters at a stop in Texas that the agency was "troubled."

"There's a lot of trouble at CDC, and it's going to require getting rid of some people in the long term in order for us to change the institutional culture," Kennedy said.

HHS leaders believe the CDC is full of hostile bureaucrats and are hoping to change the culture of the agency, people familiar with the matter said.

An HHS spokesman declined to comment but pointed to Kennedy's recent Wall Street Journal op-ed on the CDC.

The gutting of the CDC's senior ranks is the latest disruption at the agency. It followed a deadly attack by a gunman on the agency's Atlanta headquarters, proposed cuts to the agency's grants and workforce, and changes to vaccine policy made without CDC input.

After she was sworn in at the end of July, Monarez's tenure was marked by tension with HHS leaders just three weeks in.

Handpicked by Kennedy and hailed by him as a "champion of MAHA values" in the spring, Monarez objected to some of Kennedy's desired changes. When asked to remove certain CDC officials and to sign off on future recommendations that Kennedy's new slate of immunization advisers would issue, she refused. Monarez was then asked to resign at a meeting last Monday, and refused that as well before she was dismissed by the White House.

"You can't just expect to lose this kind of institutional memory and leadership and expect an organization to function, or function effectively. You just can't," said Dr. Brett Giroir, an assistant secretary for health in the first Trump administration. "It's going to take time to recover."

Some CDC employees in Atlanta have been working remotely, after a gunman, who authorities said had been critical of the Covid-19 vaccine, opened fire outside the CDC's Atlanta headquarters, killing a police officer and striking the agency's buildings. Lynda Chapman, the CDC's chief operating officer, who began in that role last week, told employees in an email that the headquarters would return to "regular on-site operations" by Monday, Sept. 15.

Sen. Bill Cassidy (R., Louisiana), who became a key vote to confirm Kennedy in February despite his reservations on Kennedy's vaccine stances, declined to opine on the firing of Monarez when asked Tuesday. "I am reserving judgment because we don't know who's right or wrong," Cassidy said. Monarez had called Cassidy last week as she faced pressure to resign, people familiar with the matter said.

The other senior CDC leaders who resigned said they felt Kennedy's leadership had compromised the agency's integrity and placed ideology over science. Dr. Demetre Daskalakis, director of the National Center for Immunization and Respiratory Diseases who resigned last week, said his subject-matter experts never briefed Kennedy on Covid-19 or measles, and he learned about changes to vaccine guidelines through social-media posts or opinion articles.

In addition to the Senate hearing scheduled for Thursday, a looming test for Kennedy's handling of the agency will be coming vaccine recommendations. Kennedy's slate of immunization committee members is due to meet later this month to discuss vaccines for Covid-19, hepatitis B, measles and more. Earlier this year, Kennedy removed all members from the panel and replaced them with his own picks.

Write to Liz Essley Whyte at liz.whyte@wsj.com, Jennifer Calfas at jennifer.calfas@wsj.com and Sabrina Siddiqui at sabrina.siddiqui@wsj.com

(END) Dow Jones Newswires

September 03, 2025 20:00 ET (00:00 GMT)

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