The 81-year-old served as director of the National Institute of Allergy and Infectious Diseases (NIAID) and chief medical adviser to President Joe Biden. He served at NIAID for 38 years and became the face of the nation’s response to COVID-19 during the pandemic. Dr. Fauci said he would leave both roles to “pursue the next chapter” of his career. In a statement, Mr. Biden said of his departure: “As he steps down from his position in the US government, I know that the American people and the entire world will continue to benefit from Dr. Fauci’s expertise in whatever if he does next. “The United States of America is stronger, more resilient and healthier because of it.” In July, Dr. Fauci said he would retire before the end of Biden’s current term. Having joined the National Institutes of Health in 1968 under President Lyndon Johnson, he was appointed director of NIAID in 1984 during the AIDS epidemic. He has since served under seven presidents, including Ronald Reagan and George W. Bush. During the coronavirus pandemic, Dr. Fauci faced criticism from Donald Trump and other conservatives who opposed imposing measures to limit the spread of COVID. Read more: First real-world study provides detailed new information on when people with COVID are infectious He also gained many fans during the pandemic, with a petition to name him as People magazine’s Sexiest Man Alive in 2020 gaining thousands of signatures. Although Dr. Fauci is stepping down from his government role, he made it clear on Monday that he will not be retiring. “I plan to pursue the next phase of my career while I still have as much energy and passion for my field,” he said. Dr. Fauci, who will turn 82 on Dec. 24, did not set a specific date for his departure.