Cost-effectiveness of voluntary HIV-1 counselling and testing in reducing sexual transmission of HIV-1 in Kenya and Tanzania

Abstract

BACKGROUND: Access to HIV-1 voluntary counselling and testing (VCT) is severely limited in less-developed countries. We undertook a multisite trial of HIV-1 VCT to assess its impact, cost, and cost-effectiveness in less-developed country settings. METHODS: The cost-effectiveness of HIV-1 VCT was estimated for a hypothetical cohort of 10000 people seeking VCT in urban east Africa. Outcomes were modelled based on results from a randomised controlled trial of HIV-1 VCT in Tanzania and Kenya. Our main outcome measures included programme cost, number of HIV-1 infections averted, cost per HIV-1 infection averted, and cost per disability-adjusted life-year (DALY) saved. We also modelled the impact of targeting VCT by HIV-1 prevalence of the client population, and the proportion of clients who receive VCT as a couple compared with as individuals. Sensitivity analysis was done on all model parameters. FINDINGS: HIV-1 VCT was estimated to avert 1104 HIV-1 infections in Kenya and 895 in Tanzania during the subsequent year. The cost per HIV-1 infection averted was US$249 and $346, respectively, and the cost per DALY saved was $12.77 and $17.78. The intervention was most cost-effective for HIV-1-infected people and those who received VCT as a couple. The cost-effectiveness of VCT was robust, with a range for the average cost per DALY saved of $5.16-27.36 in Kenya, and $6.58-45.03 in Tanzania. Analysis of targeting showed that increasing the proportion of couples to 70% reduces the cost per DALY saved to $10.71 in Kenya and $13.39 in Tanzania, and that targeting a population with HIV-1 prevalence of 45% decreased the cost per DALY saved to $8.36 in Kenya and $11.74 in Tanzania. INTERPRETATION: HIV-1 VCT is highly cost-effective in urban east African settings, but slightly less so than interventions such as improvement of sexually transmitted disease services and universal provision of nevirapine to pregnant women in high-prevalence settings. With the targeting of VCT to populations with high HIV-1 prevalence and couples the cost-effectiveness of VCT is improved significantly.