Whittles LK, Galiwango RM, Mpagazi J, Tobian AAR, Ssekubugu R, Jackson J, Peer AD, Kennedy C, Nakalanzi M, Ndyanabo A, Kigozi G, Chang LW, Serwadda D, Manabe YC, Gaydos CA, Laeyendecker O, Quinn TC, Reynolds SJ, Kagaayi J, Eaton JW, Grabowski MK. Age Patterns of HSV-2 Incidence and Prevalence in Two Ugandan Communities: A Catalytic Incidence Model Applied to Population-Based Seroprevalence Data. J Infect Dis. 2023 Nov 2;228(9):1198-1207. doi: 10.1093/infdis/jiad113. PMID: 37079374; PMCID: PMC10629710.
Abstract
Background:
Herpes simplex virus type 2 (HSV-2) is an incurable sexually transmitted infection associated with increased risk of acquiring and transmitting human immunodeficiency virus (HIV). HSV-2 is highly prevalent in sub-Saharan Africa, but population-level estimates of incidence are sparse.
Methods:
We measured HSV-2 prevalence from cross-sectional serological data among adults aged 18-49 years in 2 south-central Uganda communities (fishing, inland). We identified risk factors for seropositivity, then inferred age patterns of HSV-2 with a Bayesian catalytic model.
Results:
HSV-2 prevalence was 53.6% (n = 975/1819; 95% confidence interval, 51.3%-55.9%). Prevalence increased with age, was higher in the fishing community, and among women, reaching 93.6% (95% credible interval, 90.2%-96.6%) by age 49 years. Factors associated with HSV-2 seropositivity included more lifetime sexual partners, HIV positive status, and lower education. HSV-2 incidence peakied at age 18 years for women and 19-20 years for men. HIV prevalence was up to 10-fold higher in HSV-2-positive individuals.
Conclusions:
HSV-2 prevalence and incidence were extremely high, with most infections occurring in late adolescence. Interventions against HSV-2, such as future vaccines or therapeutics, must target young populations. Remarkably higher HIV prevalence among HSV-2-positive individuals underscores this population as a priority for HIV prevention.