WASHINGTON ‒ The White House named Jim O'Neill, a top deputy of Health and Human Services Secretary Robert F. Kennedy Jr., the acting director of the Centers for Disease Control and Prevention after firing Susan Monarez the day before.

O'Neill, who was the deputy HHS secretary, will replace Monarez on an interim basis, a Trump administration official confirmed on Aug. 28 to USA TODAY, after Monarez was fired following a dispute with Kennedy over vaccination policy. In his current role, O'Neill oversees all operations in the sprawling HHS department.

Monarez's ouster, which her attorneys have contested, came less than one month after the Senate confirmed her to the role. Her dismissal was followed by resignations from three other top CDC officials in protest of Kennedy's leadership, including his direction on vaccines. Kennedy is a longtime vaccine skeptic.

O'Neill's promotion was first reported by the Washington Post.

Attorneys for Monarez said she was targeted by Kennedy because she "refused to rubber-stamp unscientific, reckless directives and fire dedicated health experts."

The lawyers told USA TODAY she is weighing legal action to challenge her termination, arguing that only President Donald Trump can fire the CDC director ‒ a presidential-appointed, Senate-confirmed officer ‒ not a White House official or Kennedy.

White House Press Secretary Karoline Leavitt, during an Aug. 28 briefing with reporters, pushed back at that argument, claiming it was Trump who fired Monarez after she refused to step down when Kennedy asked her to resign.

"This woman has never received a vote in her life," Leavitt said. "The president has the authority to fire those who are not aligned with his mission."

Reach Joey Garrison on X @joeygarrison.

This article originally appeared on USA TODAY: Top RFK Jr. deputy Jim O'Neill named acting CDC director after previous head fired

Reporting by Joey Garrison, USA TODAY / USA TODAY

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