Combination HIV prevention among MSM in South Africa: results from agent-based modeling.
HIV prevention trials have demonstrated the effectiveness of a number of behavioral and biomedical interventions. HIV prevention packages are combinations of interventions and offer potential to significantly increase the effectiveness of any single intervention. Estimates of the effectiveness of prevention packages are important for guiding the development of prevention strategies and for characterizing effect sizes before embarking on large scale trials. Unfortunately, most research to date has focused on testing single interventions rather than HIV prevention packages. Here we report the results from agent-based modeling of the effectiveness of HIV prevention packages for men who have sex with men (MSM) in South Africa. We consider packages consisting of four components: antiretroviral therapy for HIV infected persons with CD4 count <350; PrEP for high risk uninfected persons; behavioral interventions to reduce rates of unprotected anal intercourse (UAI); and campaigns to increase HIV testing. We considered 163 HIV prevention packages corresponding to different intensity levels of the four components. We performed 2252 simulation runs of our agent-based model to evaluate those packages. We found that a four component package consisting of a 15% reduction in the rate of UAI, 50% PrEP coverage of high risk uninfected persons, 50% reduction in persons who never test for HIV, and 50% ART coverage over and above persons already receiving ART at baseline, could prevent 33.9% of infections over 5 years (95% confidence interval, 31.5, 36.3). The package components with the largest incremental prevention effects were UAI reduction and PrEP coverage. The impact of increased HIV testing was magnified in the presence of PrEP. We find that HIV prevention packages that include both behavioral and biomedical components can in combination prevent significant numbers of infections with levels of coverage, acceptance and adherence that are potentially achievable among MSM in South Africa.
Department of Biostatistics, Fielding School of Public Health, University of California Los Angeles, Los Angeles, California, United States of America.
Ron
R
Brookmeyer
Department of Biostatistics, Fielding School of Public Health, University of California Los Angeles, Los Angeles, California, United States of America.
David
D
Boren
Center for Public Health and Human Rights, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America.
Stefan D
SD
Baral
Desmond Tutu HIV Centre, University of Cape Town, Cape Town, South Africa.
Linda-Gail
LG
Bekker
HIV/AIDS, STI/TB Research Programme, Human Sciences Research Council, Port Elizabeth, South Africa, Office of the Deputy Vice Chancellor, Research and Engagement, Nelson Mandela Metropolitan University, Port Elizabeth, South Africa.
Nancy
N
Phaswana-Mafuya
Center for Public Health and Human Rights, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America.
Chris
C
Beyrer
Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, Georgia, United States of America.
Patrick S
PS
Sullivan
D019380:Anti-HIV Agents / Q000627:therapeutic use*; D003131:Combined Modality Therapy / Q000379:methods; D005820:Genetic Testing / Q000379:methods*; D015658:HIV Infections / Q000517:prevention & control*; D018451:Homosexuality, Male; D006801:Humans; D008297:Male; D008954:Models, Biological; D065129:Pre-Exposure Prophylaxis / Q000379:methods*; D021841:Safe Sex / Q000523:psychology*; D013019:South Africa
D019380:Anti-HIV Agents