President Joe Biden’s Chief Medical Adviser Anthony Fauci on Monday announced plans to step down in December after more than 50 years of government service and two years as the face of the federal government’s response to the once-in-a-lifetime COVID-19 pandemic.

Fauci, who had earlier announced plans to step down from government service but provided more specific timing Monday, has led the National Institute of Allergy and Infectious Diseases for 38 years, steering the agency through outbreaks as varied as HIV/AIDS, Zika, Ebola, and most recently COVID-19 and monkeypox. 

He has been both lionized and targeted for his leadership, facing backlash from advocates during the AIDS crisis in the 1980s and from anti-vaccine advocates and critics of controversial research during the current COVID-19 pandemic. 

But to millions of Americans, he was also a go-to source of trusted information during an unprecedented global shutdown. 

“It has been the honor of a lifetime to have led the NIAID, an extraordinary institution, for so many years and through so many scientific and public health challenges,” he said. “I am very proud of our many accomplishments. I have worked with — and learned from — countless talented and dedicated people in my own laboratory, at NIAID, at NIH and beyond.”

Fauci said he is ready to pursue the “next phase of my career,” telling The Washington Post he hopes to teach and write. 

“I want to use what I have learned as NIAID Director to continue to advance science and public health and to inspire and mentor the next generation of scientific leaders as they help prepare the world to face future infectious disease threats,” he said in a statement.

Fauci’s career has spanned seven presidential administrations, most recently as Biden’s chief medical adviser. Biden credited Fauci’s “steady hand” in saving lives around the world.

“As he leaves his position in the U.S. Government, I know the American people and the entire world will continue to benefit from Dr. Fauci’s expertise in whatever he does next,” Biden said.

National Institutes of Health acting Director Lawrence Tabak said Fauci’s departure will cause a “tectonic shift” at the NIH.

“He is the model public servant — dedicated and selfless, and a brilliant scientist and physician who is passionate about developing treatments and cures for those who are sick and suffering,” Tabak said.

A long history of government service

Fauci had been leading NIAID’s Laboratory of Immunoregulation for just one year when he first read about a new disease infecting gay men in Los Angeles. Fauci was at the forefront of the fight against HIV/AIDS and helped challenge the stigma associated with the disease.

While activists initially distrusted the government and Fauci’s response to the epidemic, many eventually embraced his work to expand access to experimental treatments. 

Fauci worked directly with AIDS patients, an experience that he said gave him post-traumatic stress syndrome as he witnessed the suffering of otherwise healthy individuals. He helped develop treatments that help people with HIV live longer, healthier lives. 

His work earned him the nation’s highest civilian honor in 2008 — the Presidential Medal of Freedom, which was awarded by President George W. Bush. 

“Before this malady even had a name, it had a fierce opponent in Dr. Anthony Fauci,” Bush said at the time. 

Fauci’s adherence to slow, rigorous scientific standards, however, sparked vocal backlash in the gay community, most notably from activist and writer Larry Kramer. Kramer accused Fauci of “murder” over NIAID’s inability to halt the epidemic, but the two later became friends. Fauci even wrote obituaries for Kramer after his death in 2020.

Fauci also helped create the President’s Emergency Plan for AIDS Relief, which helps expand access to treatments in other countries.

He has urged the government to take a similar approach in confronting stigma surrounding monkeypox, a viral disease that has had a disproportionate impact on men who have sex with men. 

“You reach out to the community. You make it very easy for them to have access to testing, to treatment, and to vaccines, as opposed to making it a situation where people are afraid to come forward for those types of things,” he told NPR recently.

The COVID-19 pandemic turned Fauci into a politically polarizing figure as the virus shut down the world and upended normal daily life, claiming more than 1 million lives. Americans struggled to navigate a new and scary health crisis while feeling their way through changing science, drastic economic disruptions, isolation and pervasive disinformation.

Many sought reassurance and guidance in Fauci’s constant news presence. But he became the focus of anger and conspiracy theories for others, particularly on the political right. “Fire Fauci” became a rallying cry among some Republicans and those protesting vaccines or simply wanting a return to normal life.

His attempts to navigate former President Donald Trump’s administration — whose officials often sought to downplay the virus’ impacts and loosen restrictions while also bringing cutting-edge vaccines to market in record time — similarly earned him fans and enemies. 

The ongoing questions around COVID-19’s origins undermined his credibility with some Republicans, like Sen. Rand Paul, R-Ky., with whom Fauci had a number of fiery confrontations.

Questions about Fauci’s decisions surrounding gain-of-function research, which can be used to manipulate and strengthen viruses, has fueled the debate around whether the virus originated naturally or accidentally leaked from a lab.

Lawmakers, reporters and internet sleuths have pored over NIAID’s funding of EcoHealth Alliance, a research institute that awarded a subgrant to the Wuhan Institute of Virology — the lab at the center of questions on the COVID’s origins. 

Fauci’s role in the public spotlight is likely far from over. Republicans have vowed to investigate Fauci and his role in the COVID-19 response if they take back control of the House or Senate this November. 

“Fauci’s resignation will not prevent a full-throated investigation into the origins of the pandemic,” Paul tweeted. “He will be asked to testify under oath regarding any discussions he participated in concerning the lab leak.”