Studies have shown that women diagnosed with herpes simplex virus-2 (HSV-2) have a higher risk for bacterial vaginosis (BV) infection. We investigated the presence of HSV-2 infections as a risk factor for incident BV infections in high risk, Human immunodeficiency virus (HIV) uninfected women enrolled in a HIV prevention trial in Durban, South Africa. The Vaginal and Oral Interventions to Control the Epidemic trial was a multicentre, double blinded, randomized controlled trial which was designed to estimate the effectiveness of daily treatment with vaginal tenofovir gel, oral tenofovir disoproxil fumarate and oral Truvada in preventing HIV-1 infection in women. Women provided samples for the diagnosis of HSV-2 and BV. The presence of HSV-2 antibodies was detected using HerpeSelect™ ELISA IgG. Bacterial vaginosis was diagnosed using the Nugent scoring system. To assess the risk of BV incidence, modelled as a time-dependent variable, we used the Andersen-Gill model with robust variance estimation and Efron methods for ties. Overall, 2750 women were enrolled in the VOICE trial at our study sites. Women who had a HSV-2 infection at enrolment were shown to be at increased risk for incident BV infections (adjusted hazard ratio 1.17, 95% CI 1.08, 1.27, p ≤ 0.001). In addition, being of a young age, being unmarried and having a partner that has other partners were significantly associated with subsequent BV infection. Our findings therefore advocate the need for strengthening STI prevention efforts among women in high burden STI settings.
Keywords: Bacterial vaginosis; HIV infection; Herpes simplex virus type -2; High-risk women.