Shafer L.A., Nsubuga R.N., Chapman R., O'Brien K., Mayanja B.N., White R.G.
Department of Internal Medicine, University of Manitoba, GF335, 810 Sherbrook Avenue, Winnipeg, MB R3E 3P5, Canada; Medical Research Council Unit on AIDS, Uganda Virus Research Institute, Entebbe, Uganda; London School of Hygiene and Tropical Medicine, London, United Kingdom
Shafer, L.A., Department of Internal Medicine, University of Manitoba, GF335, 810 Sherbrook Avenue, Winnipeg, MB R3E 3P5, Canada, Medical Research Council Unit on AIDS, Uganda Virus Research Institute, Entebbe, Uganda; Nsubuga, R.N., Medical Research Council Unit on AIDS, Uganda Virus Research Institute, Entebbe, Uganda; Chapman, R., London School of Hygiene and Tropical Medicine, London, United Kingdom; O'Brien, K., London School of Hygiene and Tropical Medicine, London, United Kingdom; Mayanja, B.N., Medical Research Council Unit on AIDS, Uganda Virus Research Institute, Entebbe, Uganda; White, R.G., London School of Hygiene and Tropical Medicine, London, United Kingdom
Objectives: Antiretroviral therapy (ART) availability in a population may influence risky sexual behaviour. We examine the potential impact of ART on the HIV epidemic, incorporating evidence for the impact that ART may have on risky sexual behaviour. Methods: A mathematical model, parameterised using site-specific data from Uganda and worldwide literature review, was used to examine the likely impact of ART on HIV epidemiologic trends. We varied assumptions about rates of initiating ART, and changes in sexual partner turnover rates. Results: Modelling suggests that ART will reduce HIV incidence over 20 years, and increase prevalence. Even in the optimistic scenario of ART enrollment beginning after just five months of infection (in HIV stage 2), prevalence is estimated to rise from a baseline of 10.5% and 8.3% among women and men, respectively, to at least 12.1% and 10.2%, respectively. It will rise further if sexual disinhibition occurs or infectiousness while on ART is slightly higher (2% female to male, rather than 0.5%). The conditions required for ART to reduce prevalence over this period are likely too extreme to be achievable. For example, if ART enrolment begins in HIV stage 1 (within the first 5 months of infection), and if risky sexual behaviour does not increase, then 3 of our 11 top fitting results estimate a potential drop in HIV prevalence by 2025. If sexual risk taking rises, it will have a large additional impact on expected HIV prevalence. Prevalence will rise despite incidence falling, because ART extends life expectancy. Conclusions: HIV prevalence will rise. Even small increases in partner turnover rates will lead to an additional substantial increase in HIV prevalence. Policy makers are urged to continue HIV prevention activities, including promoting sex education, and to be prepared for a higher than previously suggested number of HIV infected people in need of treatment.
adolescent; adult; article; controlled study; epidemic; female; health care policy; high risk behavior; highly active antiretroviral therapy; human; Human immunodeficiency virus infection; Human immunodeficiency virus prevalence; incidence; infection control; life expectancy; major clinical study; male; mathematical model; medical literature; priority journal; sexual behavior; sexual education; sexuality; Uganda; Africa; Antiretroviral therapy; epidemiologic trends; HIV/AIDS; mathematical modeling; sexual behavior; Uganda; Adolescent; Adult; Antiretroviral Therapy, Highly Active; Condoms; Female; Health Services Accessibility; HIV Seropositivity; Humans; Incidence; Male; Middle Aged; Models, Theoretical; Policy Making; Prevalence; Risk-Taking; Sex Education; Sexual Behavior; Sexual Partners; Uganda; Viral Load
B&MGF, Bill and Melinda Gates Foundation; G0501499, MRC, Bill and Melinda Gates Foundation; G0802414, MRC, Bill and Melinda Gates Foundation; MR/J005088/1, MRC, Bill and Melinda Gates Foundation