Increasing role of herpes simplex virus type 1 in first-episode anogenital herpes in heterosexual women and younger men who have sex with men, 1992-2006

The proportion of first-episode anogenital herpes due to HSV-1 significantly increased among younger MSM and heterosexual women over the 15-year period. In some clinical populations, such as young MSM and women or patients with anal disease, HSV-1 may now account for the majority of first-episode anogenital herpes.