Anthony Fauci, the leading infectious disease expert in the US, will step down from government service in December, he announced on Monday.
“It has been the honour of a lifetime to have led the [National Institute of Allergy and Infectious Diseases], an extraordinary institution, for so many years and through so many scientific and public health challenges,” Dr Fauci said in a statement.
He has led the institute since 1984 and advised seven presidents during his tenure.
As director, Dr Fauci led the US response to infectious diseases including HIV/Aids, the West Nile virus, the 2001 anthrax scares, the Ebola and Zika viruses, various bird influenza threats and, most recently, the Covid-19 pandemic.
“Because of Dr Fauci’s many contributions to public health, lives here in the United States and around the world have been saved,” said US President Joe Biden in a statement.
“As he leaves his position in the US government, I know the American people and the entire world will continue to benefit from Dr Fauci’s expertise in whatever he does next.”
Mr Biden said, as president-elect, he "immediately called" Dr Fauci to build out his Covid-19 team.
Though he will be stepping down from his positions in government, Dr Fauci said he does not intend to retire. Instead, he will look to use his 50 years of government service to mentor “the next generation” of leaders in the science community to fight threats from infectious disease.
“Thanks to the power of science and investments in research and innovation, the world has been able to fight deadly diseases and help save lives around the globe,” he said.
Dr Fauci became the face of the US response to the Covid-19 pandemic in 2020, making frequent appearances on television and at press conferences.
But he frequently found himself in conflict with former president Donald Trump, who promoted unproven therapies and pushed for returning the country to normalcy despite the continued spread of the disease.
Even as he was frozen out of Mr Trump's administration, Dr Fauci continued to promote social-distancing and mask-wearing guidelines.
A hated figure on the right, Dr Fauci became the target of political attacks and was granted a security detail after death threats were made against him and his family.
Dr Fauci's congressional hearings often grew tense, as he frequently clashed with Republicans over Covid-19 safety guidelines.