Introduction Countries in sub-Saharan Africa are scaling-up voluntary male medical circumcision (VMMC) as an HIV intervention. Emerging challenges in these programs call for increased focus on program efficiency (optimising impact while minimising cost). A novel analytic approach was developed to determine how sub-population prioritisation can increase program efficiency, as applied to Zambia.

Methods A population-level mathematical model was constructed describing the HIV epidemic and impact of VMMC programs (Age-Structured Mathematical (ASM) model). The model stratified the population according to sex, circumcision status, age group, sexual-risk group, HIV status and infection stage. A three-level conceptual framework was also developed to determine the maximum epidemic impact and program efficiency through sub-population prioritisation, based on age, geography, and risk profile.

Results In the baseline scenario, achieving 80% VMMC coverage by 2017 among males 15–49 years, 12 VMMCs are needed per HIV infection averted (effectiveness), the cost per infection averted (cost-effectiveness) is $1,089, and the number of infections averted is 306,000. Through age-group prioritisation, effectiveness ranged from 11 (20–24 age-group) to 36 (45–49 age-group) circumcisions per infection averted. Cost-effectiveness ranged from $888 (20–24 age-group) to $3,300 (45–49 age-group). Circumcising age groups 10–14, 15–19 or 20–24 achieved the largest HIV incidence rate reduction. Prioritising age groups 15–24, 15–29 or 15–34 achieved the greatest program efficiency. Through geographical prioritisation, effectiveness ranged from 9 to 12 circumcisions per infection averted. Prioritising Lusaka, the province with the highest HIV prevalence, achieved the highest effectiveness. Through risk-group prioritisation, prioritising highest risk groups achieved the highest effectiveness, with only one VMMC per infection averted, while prioritising the lowest risk group required 80 times more VMMCs.

Conclusion Epidemic impact and efficiency of VMMC programs can be improved by prioritising males in age group 15–34, geographical areas with higher HIV prevalence than the national and high sexual-risk groups.

Disclosure of interest statement This publication is based on research funded by the Bill and Melinda Gates Foundation. Infrastructure support was provided by the Biostatistics, Epidemiology, and Biomathematics Research Core at the Weill Cornell Medical College in Qatar.

The content of this manuscript is the sole responsibility of the authors. The information provided here is not official US Government information and does not necessarily represent the views or positions of United States Agency for International Development, the United States Government, or the Bill and Melinda Gates Foundation.