Staff at the US Centres for Disease Control and Prevention have staged a mass walkout in a show of support for three top officials who resigned in protest this week.

CDC boss Susan Monarez quit the agency this week, less than a month after being sworn in, while chief medical officer Debra Houry and US National Centre for Immunisation and Respiratory Diseases director Demetre Daskalakis also resigned.

US National Centre for Emerging and Zoonotic Infectious Diseases director Daniel Jernigan has also quit, days after the agency reported the first US human case of screwworm linked to an ongoing outbreak in Central America.

“Susan Monarez is no longer director of the Centres for Disease Control and Prevention. We thank her for her dedicated service to the American people,” the US Department of Health and Human Services wrote in a statement posted on social media.

Daskalakis, Houry and Jernigan resigned in protest at the ousting of Monaraz. They went to CDC headquarters in Atlanta to clear out their offices on Thursday (US time) and, as they left the building, were followed out by hundreds of workers who cheered them and thanked them for their work.

The Washington Post first reported Monarez was being ousted and on her way out earlier on Wednesday, citing multiple Trump administration officials familiar with the matter.

White House press secretary Karoline Leavitt said US President Donald Trump had fired Monarez because she was “not aligned with the President’s mission to make America healthy again.”

“It was President Trump who was overwhelmingly reelected on November 5,” Leavitt said.

“This woman has never received a vote in her life, and the President has the authority to fire those who are not aligned with his mission.”

The White House said US Deputy Health and Human Services Secretary Jim O’Neill would be acting CDC director, with a replacement for Monarez to be announced “very soon”.

Monarez, a federal government scientist, was confirmed by the US Senate on July 29 to lead the CDC after Trump nominated her earlier in the year. She was sworn in by Trump’s top health official, Robert F. Kennedy jr on July 31.

Her departure from the agency follows a shooting at the CDC’s headquarters in Atlanta, Georgia, earlier in August.

Monarez was the Trump administration’s second nominee for the role. In March, Trump withdrew his nomination of former Republican congressman and vaccine critic Dave Weldon, a Kennedy ally, just hours before his scheduled confirmation hearing.

Since being named the top US health official, Kennedy has targeted vaccine policy, and in May withdrew a federal recommendation for Covid shots for pregnant women and healthy children.

He followed up in June by firing all members of the CDC’s expert vaccine advisory panel, which recommends how they are used and by whom, and replacing them with hand-picked advisers including fellow anti-vaccine activists.

Kennedy has made major decisions on vaccines in the absence of a CDC director while Monarez awaited confirmation and continued to do so afterwards. Her departure came on the same day that Kennedy announced changes to Covid vaccine eligibility.

-with AAP