Dr. Anthony Fauci laughs while speaking at a White House briefing on Thursday. Fauci, President Biden’s chief medical adviser on COVID-19, says he rejoiced when the new president declared that “science and truth” would guide the nation’s policies toward the pandemic.

Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, laughs while speaking in the James Brady Press Briefing Room at the White House, Thursday, Jan. 21, 2021, in Washington. (AP Photo/Alex Brandon)