• Posted September 2, 2025

Jim O’Neill Steps in as Acting CDC Chief Amid Firing, Resignations

TUESDAY, Sept. 2, 2025 (HealthDay News) — The U.S. Centers for Disease Control and Prevention (CDC) is entering a transition period as Jim O’Neill, deputy secretary at the Department of Health and Human Services (HHS), steps in as acting director. 

The announcement came in a letter to CDC employees from HHS Secretary Robert F. Kennedy Jr.

O’Neill, who joined HHS in June, has experience in both the tech and public health sectors. Before his government roles, he spent years investing in biotech and technology startups, including time with the Thiel Foundation and Thiel Fellowship, founded by entrepreneur Peter Thiel, CNN reported. 

He also previously served at HHS during the administration of George W. Bush, focusing on food regulations and emergency response.

His appointment dovetails a challenging period for the CDC. Director Susan Monarez was recently fired after clashing with RFK Jr. over vaccine policy. Several senior officials — including the agency’s chief medical officer, head of vaccines and data chief — resigned in protest.

Staff gathered outside the CDC’s Atlanta headquarters Thursday to honor some of the departing leaders, CNN said in a report.

O’Neill toured the CDC campus with Monarez and Kennedy last month following a tragic shooting that left DeKalb County Police Officer David Rose dead and damaged several buildings.

At his HHS confirmation hearing in May, O’Neill voiced strong support for vaccines, according to CNN, stating, “I support the CDC vaccine schedule." 

He also pledged to focus on transparency, prevention and modernizing current policies.

“Our health care system is difficult to navigate, and it prioritizes pills over prevention,” he said at the hearing.

“If confirmed, I’ll help reform outdated rules, pursue transparency and gold standard science, and champion healthy lifestyles and prevention so Americans can thrive,” he said at the time.

More information

Learn more about the role of the U.S. Centers for Disease Control and Prevention.

SOURCE: CNN; Aug. 29, 2025

“If confirmed, I’ll help reform outdated rules, pursue transparency and gold standard science, and champion healthy lifestyles and prevention so Americans can thrive.”

More information

Learn more about the role of the CDC.

SOURCE: CNN, Aug. 29, 2025