Increasing proportion of herpes simplex virus type 1 as a cause of genital herpes infection in college students

Sex Transm Dis. 2003 Oct;30(10):797-800. doi: 10.1097/01.OLQ.0000092387.58746.C7.


A retrospective review of genital herpes simplex virus (HSV) isolates collected in a university student health service over a 9-year period showed that an increasing proportion of isolates were HSV-1 rather than HSV-2. HSV-1 accounted for 78% of all genital isolates in this population by 2001, compared with 31% of isolates in 1993.

Background: Herpes simplex virus (HSV) type 1 is usually thought to cause less than 30% of genital herpes infections in the United States, but the proportion of infections resulting from HSV-1 is increasing in some populations.

Goal: The goal was to review the relative proportion of HSV-1 and HSV-2 as the cause of newly diagnosed genital herpes infections in a population of U.S. college students and to assess trends in the change of this proportion over time.

Study design: Genital HSV isolates collected at a university student health service from 1993 to 2001 (n = 499) were reviewed retrospectively. Analyses included comparisons of isolates by HSV type, age group, and sex.

Results: The proportion of newly diagnosed genital herpes infections resulting from HSV-1 increased from 31% in 1993 to 78% in 2001 (P <0.001, linear trend P <0.001). HSV-1 was more common in females than males, but increases were noted for both sexes. HSV-1 was more common in persons aged 16 to 21 than in persons aged 22 or older.

Conclusions: HSV-1 has become the most common cause of newly diagnosed genital herpes infections in this population of college students and reflects a reversal of the usual HSV-1/HSV-2 ratio.

MeSH terms

  • Adolescent
  • Adult
  • Female
  • Herpes Genitalis / epidemiology*
  • Herpes Genitalis / virology*
  • Herpesvirus 1, Human / isolation & purification*
  • Herpesvirus 2, Human / isolation & purification*
  • Humans
  • Male
  • Midwestern United States / epidemiology
  • Students / statistics & numerical data
  • Universities