The herpes simplex virus comes in two strains, HSV-1 and HSV-2. HSV-1. This STD most commonly causes oral herpes (cold sores) and HSV-2 genital herpes though both can cause infection of the mouth or genitals. The HSV viruses are large double-stranded DNA viruses and members of the Herpesviridae family which also includes Epstein-Barr Virus, the Chickenpox… Continue reading