Socio-demographic and behavioral correlates of herpes simplex virus type 1 and 2 infections and co-infections among adults in the USA.

Objectives: Although herpes simplex virus (HSV)-1 and HSV-2 may co-exist and interact, some epidemiologic features including geographical distribution, secular trends, route of transmission, and established risk factors may distinguish these HSV sub-types. With recent data indicating a link between genital herpes and either strain, a re-evaluation of risk factors for HSV-1/HSV-2 infection and co-infection is needed.

Methods: We used the 1999-2004 National Health and Nutrition Examination Study (NHANES) data and logistic regression modeling to identify socio-demographic and behavioral risk factors that can independently predict HSV-1/HSV-2 infection and co-infection.

Results: Approximately 48% were positive for HSV-1 alone, 7% were positive for HSV-2 alone and 12% were co-infected with HSV-1 and HSV-2. History of genital herpes was found in individuals infected with either or both HSV sub-types. Whereas age, sex, race, and level of education independently predicted all three outcomes, lifetime sexual activity as well as use of tobacco products and recreational drugs mainly correlated with HSV-2 infection and HSV-1/HSV-2 co-infection. Lifetime use of alcohol was not consistently associated with HSV-1/HSV-2 infection and co-infection.

Conclusions: Sexual activity played an important role for HSV-2 and was potentially important for HSV-1, with implications for healthcare practice and vaccine development.