The White House confirmed Wednesday that Susan Monarez, the recently appointed head of the Centers for Disease Control and Prevention (CDC), has been fired after refusing to resign in the middle of a standoff with Health and Human Services Secretary Robert F. Kennedy Jr.

Monarez, a veteran health scientist and civil servant, had led the CDC for less than a month before Kennedy’s department announced on X that she “is no longer director.” The dispute centered on Kennedy’s push to overhaul U.S. vaccine policy — a shift Monarez reportedly resisted.

The confrontation has triggered broader upheaval within the agency. According to a union representing CDC staff, at least five other senior officials have also resigned in protest.

Monarez’s attorneys insisted she had not stepped down and questioned the legality of her dismissal. “As a presidential appointee, Senate-confirmed officer, only the president himself can fire her,” her legal team said, calling the notification she received from a White House staffer “legally deficient.”

The White House, however, defended the move. “As her attorney’s statement makes abundantly clear, Susan Monarez is not aligned with the President’s agenda of Making America Healthy Again,” spokesman Kush Desai said in an email, adding that Monarez had been terminated after refusing to resign.

Monarez’s lawyers countered that Kennedy was “weaponizing public health for political gain and putting millions of American lives at risk.”

The Washington Post, which first reported the dismissal, said Kennedy had pressured Monarez to resign after she declined to endorse his controversial vaccination policy changes.