Official websites use .gov A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
CAPTION: Virologist Harold E. Varmus, MD, professor of microbiology, biochemistry and biophysics at the University of California, San Francisco, and American Cancer Society Professor of Molecular Virology.