A 15-year study of the impact of community antiretroviral therapy coverage on HIV incidence in Kenyan female sex workers
Department of Medicine, Epidemiology, and Global Health, University of Washington, Box 359909, 325 9th Avenue, Seattle, WA, United States; Department of Epidemiology, University of Washington, Seattle, WA, United States; Department of Global Health, University of Washington, Seattle, WA, United States; Department of Biostatistics, University of Washington, Seattle, WA, United States; Institute of Tropical and Infectious Diseases, University of Nairobi, Nairobi, Kenya; Department of Medical Microbiology, University of Nairobi, Nairobi, Kenya; Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, WA, United States; Division of Public Health Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA, United States; Division of Vaccine and Infectious Disease, Fred Hutchinson Cancer Research Center, Seattle, WA, United States; National AIDS and STD Control Programme, Nairobi, Kenya; Mombasa County Department of Policy and Research, Mombasa, Kenya
Objective: To test the hypothesis that increasing community antiretroviral therapy (ART) coverage would be associated with lower HIV incidence in female sex workers (FSWs) in Mombasa District, Kenya. Design: Prospective cohort study. Methods: From 1998 to 2012, HIV-negative FSWs were asked to return monthly for an interview regarding risk behavior and testing for sexually transmitted infections including HIV. We evaluated the association between community ART coverage and FSW's risk of becoming HIV infected using Cox proportional hazards models adjusted for potential confounding factors. Results: One thousand, four hundred and four FSWs contributed 4335 woman-years of follow-up, with 145 acquiring HIV infection (incidence 3.35/100 woman-years). The ART rollout began in 2003. By 2012, an estimated 52% of HIV-positive individuals were receiving treatment. Community ART coverage was inversely associated with HIV incidence (adjusted hazard ratio 0.77; 95% confidence interval 0.61-0.98; P=0.03), suggesting that each 10% increase in coverage was associated with a 23% reduction in FSWs' risk of HIV acquisition. Community ART coverage had no impact on herpes simplex virus type-2 incidence (adjusted hazard ratio 0.97; 95% confidence interval 0.79-1.20; P=0.8). Conclusion: Increasing general population ART coverage was associated with lower HIV incidence in FSWs. The association with HIV incidence, but not herpes simplex virus type-2 incidence, suggests that the effect of community ART coverage may be specific to HIV. Interventions such as preexposure prophylaxis and antiretroviral-containing microbicides have produced disappointing results in HIV prevention trials with FSWs. These results suggest that FSWs' risk of acquiring HIV infection might be reduced through the indirect approach of increasing ART coverage in the community. Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved.
anti human immunodeficiency virus agent; adolescent; adult; antiviral therapy; Article; CD4 lymphocyte count; cohort analysis; community care; female; follow up; herpes simplex; Herpes simplex virus 2; high risk behavior; human; Human immunodeficiency virus 1 infection; Human immunodeficiency virus 2 infection; Human immunodeficiency virus prevalence; incidence; Kenya; Kenyan; priority journal; prospective study; prostitution; sexually transmitted disease; virus load