FILE PHOTO: An electron microscopic (EM) image shows mature, oval-shaped monkeypox virus particles as well as crescents and spherical particles of immature virions, obtained from a clinical human skin sample associated with the 2003 prairie dog outbreak in this undated image obtained by Reuters on May 18, 2022. Cynthia S. Goldsmith, Russell Regnery/CDC/Handout via REUTERS
