Predeominace of Herpes Simplex Virus Type 1 from Patients with Genital Herpes in Nova Scotia

The epidemiology of genital herpes is changing with evidence to suggest an increasing incidence of herpes simplex virus type 1 (HSV‐1) infections. The results of 6529 HSV genital cultures taken between April 1998 and December 2001 were reviewed. Overall, HSV‐1 was recovered more often than HSV‐2; 1213 versus 1045. This trend was particularly striking in young women 30 years of age or less, in whom 70.8% of isolates were HSV‐1. In men of the same age range, 45% of isolates were HSV‐1. The proportion of women with HSV‐1 declined from 73.7% in those younger than 31 years of age to 4.5% in those older than 60 years of age. These observations have important implications. The decline in the relative proportion of HSV‐1 isolates from young adults may be the result of changing sexual practices, changing susceptibility or increased exposure to HSV‐1 during vaginal intercourse. In this setting HSV‐2 vaccines may be less likely to produce the desired reduction in the overall prevalence of genital herpes infections.