| rise in seroprevalence of herpes simplex virus type 1 among highly sexual active homosexual men and an increasing association between herpes simplex virus type 2 and hiv over time (1984-2003). | herpes simplex virus type 1 and type 2 (hsv-1 and hsv-2) are both highly prevalent. the rate of genital hsv-1 transmission is reportedly increasing over time. hsv-2 is considered to be an important risk factor for hiv transmission. we therefore studied changes in the hsv-1 and hsv-2 prevalence in a large cohort of men who have sex with men (msm) over a 20-year time period. | 2007 | 17929177 |