The nation's top infectious disease expert will leave the federal government in December after more than 50 years of service.

Fauci was the director of the National Institute of Allergy and Infectious Diseases and the chief of the NIAID Laboratory of Immunology. Before the coronaviruses hit, he was a leader in the federal response to HIV/AIDS.

Fauci said in a statement that he would be leaving the positions in December to pursue the next chapter of his career.

Fauci was the face of the government's response to COVID-19, with frequent appearances on television news and daily press conferences with White House officials. Fauci fell out of favor with Trump and his officials when his public caution clashed with the former president's desire to return to normal.

Fauci was marginalized by the Trump administration and kept out of major decisions about the federal response, but he continued to speak out in public and advocated face coverings in public.

He was the target of political attacks and death threats and was given a security detail.

Fauci was asked by Biden to stay on in his administration. The president said that Fauci has touched all Americans with his work. His public service was appreciated by me. The United States of America is a better place to live in because of him.

Fauci said he would continue working even though he retired from federal service. He wants to use what he has learned as NIAID Director to continue to advance science and public health and to inspire and mentor the next generation of scientific leaders.