1st Case of Sexually Transmitted Virulent Monkeypox Strain Detected in Congo: WHO

The virulent strain has a fatality rate of about 10 percent compared to the less-severe strain, with both having spread mostly among gay men.

This 2003 electron microscope image made available by the Centers for Disease Control and Prevention shows mature, oval-shaped monkeypox virions (L) and spherical immature virions (R) obtained from a sample of human skin associated with the 2003 prairie dog outbreak. Cynthia S. Goldsmith, Russell Regner/CDC via AP

The World Health Organization (WHO) has identified the first incidence of sexual transmission of a severe strain of monkeypox (mpox), reported in a man who engaged in homosexual activity.

The first known case of sexually transmitted Clade I monkeypox virus (MPXV) infection was identified in a Belgian resident who was visiting the Democratic Republic of the Congo, the WHO said in a Nov. 23 post. There are two known strains of MPXV: Clade I and Clade II, with the former being the more virulent strain.