A top pandemic expert is leaving the Trump administration amid the coronavirus crisis

• Rear Adm. Timothy Ziemer, a top expert on pandemics, is leaving the Trump administration, Politico reported on Tuesday.
• Ziemer, who previously led the National Security Council's global health unit, has been at USAID as senior deputy assistant administrator.
• The NSC's global health security team was scrapped under Trump in May 2018, and never reinstated.
• Critics point to the move as one of the key ways in which the Trump administration left the US unprepared for coronavirus.
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The Trump administration just lost one of its top experts on pandemics as the death toll from coronavirus in the US continues to rise, Politico reported on Tuesday.

Rear Adm. Timothy Ziemer spearheaded the National Security Council's (NSC) global health security unit, which was responsible for leading the US response to a pandemic, until the Trump administration disbanded it in May 2018.

Ziemer went to USAID, serving as senior deputy assistant administrator, after the NSC's global health unit was disbanded. His decision to depart the US government was "very difficult and emotional," according to a note obtained by Politico. The exact reasons behind Ziemer's departure are unclear, and there are few details on the nature of his role at USAID in relation to coronavirus.

The NSC's global health security team — established under the Obama administration in 2015 and officially known the Directorate for Global Health and Security and Biodefense — was scrapped under then-National Security Adviser John Bolton. Among other decisions, the move has been pointed to by critics of the administration as one of the myriad ways the US was left less prepared for a pandemic under Trump's leadership. The unit was never reinstated.

Dr. Anthony Fauci, the nation's top expert on infectious disease who's also on the White House coronavirus task force, in March told House lawmakers it would be nice if the global health unit still existed.

"We worked very well with that office. It would be nice if the office was still there," Fauci, the director of the National Institute of Allergy and Infectious Diseases, said during a House Oversight and Reform Committee hearing.

Ziemer had a long career in public service, particularly in relation to public health, leading the President's Malaria Initiative under Presidents George W. Bush and Barack Obama before joining the NSC in 2017.