The cost and cost-effectiveness of alternative strategies to expand treatment to HIV-positive South Africans: scale economies and outreach costs

This repository item contains a single issue of the Health and Development Discussion Papers, an informal working paper series that began publishing in 2002 by the Boston University Center for Global Health and Development. It is intended to help the Center and individual authors to disseminate work that is being prepared for journal publication or that is not appropriate for journal publication but might still have value to readers.The South African government is currently discussing various alternative approaches to the further expansion of antiretroviral treatment (ART) in public-sector facilities. We used the EMOD-HIV model, a HIV transmission model which projects South African HIV incidence and prevalence and ARV treatment by age-group for alternative combinations of treatment eligibility criteria and testing, to generate 12 epidemiological scenarios. Using data from our own bottom-up cost analyses in South Africa, we separate outpatient cost into nonscale- dependent costs (drugs and laboratory tests) and scale-dependent cost (staff, space, equipment and overheads) and model the cost of production according to the expected future number and size of clinics. On the demand side, we include the cost of creating and sustaining the projected incremental demand for testing and treatment. Previous research with EMOD-HIV has shown that more vigorous recruitment of patients with CD4 counts less than 350 is an advantageous policy over a five-year horizon. Over 20 years, however, the model assumption that a person on treatment is 92% less infectious improves the cost-effectiveness of higher eligibility thresholds, averting HIV infections for between $1,700 and $2,800, while more vigorous expansion under the current guidelines would cost more than $7,500 per incremental HIV infection averted. Based on analysis of the sensitivity of the results to 1,728 alternative parameter combinations at each of four discount rates, we conclude that better knowledge of the behavioral elasticities could reduce the uncertainty of cost estimates by a factor of 4 to 10