1. 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
Department of Epidemiology
Emory University
Atlanta, GA, USA

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

3. 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

4. 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

5. 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).

6. 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 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) UK ; 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

7. 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
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
0.5**
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
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