Trump to install Jim O’Neill as acting CDC chief after firing Susan Monarez

The Trump administration is set to appoint Jim O’Neill as acting head of the Centers for Disease Control and Prevention (CDC), after ousting Director Susan Monarez less than a month into her tenure.

Reports from The Washington Post and The Associated Press confirmed O’Neill’s selection on Thursday, citing White House officials who said Monarez was removed after clashing with President Donald Trump’s team over vaccine policy and scientific integrity.

O’Neill, currently deputy to Health and Human Services (HHS) Secretary Robert F Kennedy Jr, is expected to take charge immediately.

Sources close to Monarez said she refused to endorse directives she believed were “illegal” or “in the face of science.” Former acting CDC chief Richard Besser told reporters:

“She said there were two things she would never do … and she was asked to do both.”

Monarez herself said she would not “rubber-stamp unscientific, reckless directives and fire dedicated health experts.” Several senior CDC officials resigned in solidarity this week, warning that the agency’s mission to protect public health was being undermined.

Kennedy, a longtime vaccine skeptic, has moved to reshape the CDC since taking office, purging its vaccine advisory board and removing staff he views as hostile to his agenda. On Fox News, he said the CDC had spread “misinformation” during COVID-19 and required “strong leadership” aligned with Trump’s “broad ambitions.”

White House Press Secretary Karoline Leavitt defended the dismissal:

“Her lawyer’s statement made it abundantly clear she was not aligned with the president’s mission to make America healthy again … The president fired her, which he has every right to do.”

Tensions inside the agency spiked after a gunman, who blamed vaccines for his health issues, attacked CDC headquarters in Atlanta earlier this month, killing one police officer before taking his own life.

The CDC’s union, AFGE Local 2883, said the tragedy reflected “months of mistreatment, neglect, and vilification” under Kennedy. A group of former employees, Fired But Fighting, accused him of spreading “continuous lies about science and vaccine safety.”

Despite the backlash, the administration is pressing ahead with its overhaul of the health agency, as O’Neill prepares to take over one of the most politically sensitive jobs in US public health.