Dr. Anthony Fauci, who played a critical role in steering humanity through the two pandemics of our time, AIDS and COVID-19, announced Monday he is stepping down from his role in the federal government. As of December, he will leave the position he's held for 38 years as the director of the National Institute of Allergy and Infectious Diseases, as well as his job as chief of the NIAID Laboratory of Immunoregulation, and his role as Chief Medical Advisor to President Joe Biden.

The straight-talking scientist and physician was the government's top infectious disease doctor for decades, and one of the few scientists that many Americans knew by name. Fauci, 81, served under seven U.S. presidents and helped lead the country through numerous health crises. He was instrumental in combatting the AIDS epidemic, starting as the youthful director of NIAID in the early 1980s.