Risk factors of herpes simplex type 1 (HSV-1) infection and lifestyle factors associated with HSV-1 manifestations

This study investigated risk factors for herpes simplex virus type 1 (HSV-1) infection in a population of university students in Germany and Spain. In addition, factors associated with the occurrence of oral lesions were studied. Serum samples were collected from 596 Spanish students from the Navarra Public University in Pamplona and 174 German students from the University of Bielefeld aged 17–41 years and tested by a HSV-1 type-specific immunoassay using monoclonal antibody-selected gG1 as antigen. Information on clinical manifestations and risk factors were obtained by a standardized questionnaire. The rate of HSV-1 infection was 55.3 and 27.4% of these infected students reported having had oral lesions within the last 12 months. Prevalence of HSV-1 infection did not differ between study sites, and did not vary according to gender or age. Students with coitus experience were more likely to be infected with HSV-1 (Odds ratio (OR), 1.88; 95%CI: 1.31–2.69), while other lifestyle factors were not associated with HSV-1 infection. Risk factors for the occurrence of oral lesions included HSV-1 seropositivity (OR: 6.90; 95%CI: 3.84–12.37) and a higher level of perceived stress, as measured by the Cohen scale of perceived stress (OR: 1.79; 95%CI: 1.15–2.78). Drinking alcohol was found to be a protective factor (OR: 0.59; 95%CI: 0.37–0.93). There was no difference in the clinical pattern and course of infection between the young adults in Germany and Spain. We conclude, that lifestyle factors appear to play an important role in the epidemiology and clinical manifestations of HSV-1.