Rochelle Walensky, Director of the U.S. Centers for Disease Control and Prevention (CDC), and Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, listen during a Senate Health, Education, Labor, and Pensions Committee hearing at the Dirksen Senate Office Building in Washington, D.C., U.S., July 20, 2021. Stefani Reynolds/Pool via REUTERS