"152 Figure 14 . H ow STD’s Affect Populations in the United States Figure 15 . Ages affected by chlamydia and gonorrhea infections Genital Herpes Genital herpes is a contagious infection caused by the herpes simplex virus (HSV). There are two different strains, or types, of HSV: herpes simplex virus type 1 (HSV - 1) and type 2 (HSV - 2). Both can cause genital herpes, although most cases of genital herp es are caused by HSV - 2. When symptomatic, HSV - 1 usually appears as fever blisters or cold sores on the lips, but it can also infect the genital region through oral - genital or genital - genital contact. Symptomatic HSV - 2 typically causes painful, watery skin blisters on or around the genitals"