Department of Epidemiology Modeling the cost-per-HIV infection averted by couples’ voluntary HIV counseling and testing (CVCT) in six African countries Kristin M. Wall, PhD kmwall@emory.edu Department of Epidemiology Emory University Atlanta, GA, USA

Conflict of Interest Disclosure The authors have no conflicts of interest due to financial or personal relationships that might be perceived to cause bias.

CVCT previously shown to be financially cost-effective in Zambia, 2010-2014 Presented at AIDS 2014, briefly: 172,981 couples in 73 government clinics tested ($52/couple) Repeat testing for concordant negative couples, discordant couples on/off ART ART use in HIV+ partners increased from 20% to 43% in discordant couples after CVCT 63-84% reductions in HIV seroincidence before vs. after CVCT $440 per HIV infection averted (donor/payer perspective) Objective: To estimate the cost-per-HIV infection averted (CHIA) by CVCT in 6 sub-Saharan African countries 84% discordant couples on ART 78% discordant couples no ART 63% concordant HIV- couples

Modeling Assumptions Range of CVCT effect inputs: Prevention impacts observed in Zambia (63-84%) Conservative estimates: 50% reduction Range of cost inputs conceptualized within 4 implementation phases: Initiation: 10% of couples are tested at $75/couple Expansion: additional 10% of couples tested at $50/couple Mature: additional 60% of couples tested at $25/couple Maintenance: 20% of residual and new couples tested at $10/couple 5% of HIV+ partners will initiate therapeutic ART/year Country-specific parameters: Published literature

Countries with decreasing prevalence of HIV and discordance Cost-per-HIV infection averted by CVCT (‘mature’ and ‘expansion’ phases not shown) 5: 5-year time horizon 10: 10-year time horizon Les: Lesotho, Zim: Zimbabwe, Ken: Kenya, Tanz: Tanzania; IC: Ivory Coast; SL: Sierra Leone INITIATION PHASE MAINTENANCE PHASE CVCT CHIA range: $35 in Lesotho, assuming10-years of impact and observed CVCT effectiveness $3,076 in Sierra Leone, assuming 5-years of impact and conservative CVCT effectiveness Countries with decreasing prevalence of HIV and discordance CONCLUSIONS CVCT was cost-effective, more so in high prevalence countries. CVCT should be a funding and policy priority within combination prevention and treatment packages. CHIAs were lowest in areas with high prevalence of HIV and HIV discordance (as in Southern Africa) and highest in areas with lower prevalence of HIV and HIV discordance (as in Western Africa).

Funding & Acknowledgements This document was produced under Arise—Enhancing HIV Prevention Programs for At-Risk Populations, through financial support provided by the Canadian Government through Foreign Affairs, Trade and Development Canada (DFATD, formerly CIDA) with technical support from PATH (CID.1450-08863-SUB). Arise implements innovative HIV prevention initiatives for vulnerable communities, with a focus on determining cost-effectiveness through rigorous evaluations. This study was also supported by the UK Department for International Development (DFID) UK202340-102; the International AIDS Vaccine Initiative with the generous support of the American people through the United States Agency for International Development (USAID); National Institutes of Health grants R01 MH66767, R01 HD40125, and R01 MH95503; the AIDS International Training and Research Program Fogarty International Center (D43 TW001042); the Emory Center for AIDS Research (P30 AI050409); and the Centers for Disease Control (U2GPS00758). The contents are the responsibility of the authors and do not necessarily reflect the views of sponsors, who had no role in study design, data collection and analysis, or preparation of the findings. Rwanda Zambia HIV Research Group (RZHRG) Co-authors: Bellington Vwalika Robert Yohnka Joseph Mulenga Joseph Abdallah Rachel Parker Susan Allen Mubiana Inambao Tyronza Sharkey William Kilembe Amanda Tichacek Etienne Karita Eric Hunter

Model parameters SOUTHERN AFRICA EAST-CENTRAL AFRICA WESTERN AFRICA   Lesotho ZIMBABWE Kenya Tanzania ivory coast sierra leone Adult Population (ages 15-64, in millions) 1.31-3 8.31-3 25.91-3 25.62-4 11.91-3 3.42,3 Adult population in couples (%) 48%4 57%4 55%4 59%4 52%4 69%4 Discordant couples among all couples (%) 17%4 13%4 6%4 2%4 Concordant negative couples among all couples (%) 65%4 79%4 91%4 93%4 98%4 Adults on ART of all HIV+ adults (%) 29%5,6 48%5,6 42%5,6 41%5,6 36%5,6 17%5,6 Uncounseled incidence, concordant HIV- couples (per 100 CY) 2* 1* 0.87-9 0.67-10 0.5** 0.4** Uncounseled incidence, non-ART using discord couples (per 100 CY) 2511,12 157-9,11 108,10,11 711 Uncounseled incidence, ART using discordant couples (per 100 CY) 1.713 1.7 13  *Estimated based on findings from the Copperbelt implementation and country-specific HIV prevalence **Estimated based on published findings from East-Central Africa and country-specific HIV prevalence CY: couple year; ART: antiretroviral treatment; “uncounseled” indicates before CVCT 1.World Population Prospects: The 2012 Revision. United Nations, 2015. (Accessed April 2, 2015, at http://esa.un.org/wpp/unpp/panel_indicators.htm.) 2.The World Factbook 2011. 2011. (Accessed April 3, 2015, at https://http://www.cia.gov/library/publications/the-world-factbook/fields/2010.html.) 3.Indicators. The World Bank Group, 2015. (Accessed April 3, 2015, at http://data.worldbank.org/indicator/.) 4.ICF International. (Accessed November 1, 2014, at http://www.measuredhs.com/.) 5.AIDSinfo. 2014. (Accessed April 2, 2015, at http://www.unaids.org/en/dataanalysis/datatools/aidsinfo/.) 6.Antiretroviral therapy coverage: Data and estimates by country WHO, 2014. (Accessed April 2, 2015, at http://apps.who.int/gho/data/node.main.626?lang=en.) 7.Carpenter LM, Kamali A, Ruberantwari A, et al . Rates of HIV-1 transmission within marriage in rural Uganda in relation to the HIV sero-status of the partners. Aids 1999;13:1083-9. 8.Quinn TC, Wawer MJ, Sewankambo N, et al. Viral load and heterosexual transmission of human immunodeficiency virus type 1. Rakai Project Study Group. N Engl J Med 2000;342:921-9. 9.Serwadda D, Gray RH, Wawer MJ, et al. The social dynamics of HIV transmission as reflected through discordant couples in rural Uganda. Aids 1995;9:745-50. 10.Hugonnet S, Mosha F, Todd J, et al. Incidence of HIV infection in stable sexual partnerships: a retrospective cohort study of 1802 couples in Mwanza Region, Tanzania. Journal of acquired immune deficiency syndromes (1999) 2002;30:73-80. 11.Chemaitelly H, Awad SF, Abu-Raddad LJ. The risk of HIV transmission within HIV-1 sero-discordant couples appears to vary across sub-Saharan Africa. Epidemics 2014;6:1-9. 12.Hira SK, Nkowane BM, Kamanga J, et al. Epidemiology of human immunodeficiency virus in families in Lusaka, Zambia. Journal of acquired immune deficiency syndromes (1999) 1990;3:83-6. 13.Anglemyer A, Horvath T, Rutherford G. Antiretroviral therapy for prevention of HIV transmission in HIV-discordant couples. JAMA : 2013;310:1619-20.