Extent to which low-level use of antiretroviral treatment could curb the AIDS epidemic in sub-Saharan Africa

Background Despite growing international pressure to provide HIV-1 treatmen t to less-developed countries, potential demographic and epidemiological im pacts have yet to be characterised. We modelled the future impact of antire troviral use in South Africa from 2000 to 2005. Methods We produced a population projection model that assumed zero antiret roviral use to estimate the future demographic impacts of the HIV-1 epidemi c. We also constructed four antiretroviral-adjusted scenarios to estimate t he potential effect of antiretroviral use. We modelled total drug cost, cos t per life-year gained, and the proportion of per-person health-care expend iture required to finance antiretroviral treatment in each scenario. Findings With no antiretroviral use between 2000 and 2005, there will be ab out 276 000 cumulative HIV-1-positive births, 2 302 000 cumulative new AIDS cases, and the life expectancy at birth will be 46.6 years by 2005. By con trast, 110 000 HIV-1-positive births could be prevented by short-course ant iretroviral prophylaxis, as well as a decline of up to 1 year of life expec tancy. The direct drug costs of universal coverage for this intervention wo uld be US$54 million-less than 0.001% of the per-person health-care expendi ture. In comparison, triple-combination treatment for 25% of the HIV-1-posi tive population could prevent a 3.1-year decline in life expectancy and mor e than 430 000 incident AIDS cases. The drug costs of this intervention wou ld, however, be more than $19 billion at present prices, and would require 12.5% of the country's per-person healthcare expenditure. Interpretation Although there are barriers to widespread HIV-1 treatment, l imited use of antiretrovirals could have an immediate and substantial impac t on South Africa's AIDS epidemic.