Scaling up antiretroviral therapy in South Africa: the impact of speed on survival.

Background: Only 33% of eligible human immunodeficiency virus (HIV)-infected patients in South Africa receive antiretroviral therapy (ART). We sought to estimate the impact of alternative ART scale-up scenarios on patient outcomes from 2007-2012.

Methods: Using a simulation model of HIV infection with South African data, we projected HIV-associated mortality with and without effective ART for an adult cohort in need of therapy (2007) and for adults who became eligible for treatment (2008-2012). We compared 5 scale-up scenarios: (1) zero growth, with a total of 100,000 new treatment slots; (2) constant growth, with 600,000; (3) moderate growth, with 2.1 million; (4) rapid growth, with 2.4 million); and (5) full capacity, with 3.2 million.

Results: Our projections showed that by 2011, the rapid growth scenario fully met the South African need for ART; by 2012, the moderate scenario met 97% of the need, but the zero and constant growth scenarios met only 28% and 52% of the need, respectively. The latter scenarios resulted in 364,000 and 831,000 people alive and on ART in 2012. From 2007 to 2012, cumulative deaths in South Africa ranged from 2.5 million under the zero growth scenario to 1.2 million under the rapid growth scenario.

Conclusions: Alternative ART scale-up scenarios in South Africa will lead to differences in the death rate that amount to more than 1.2 million deaths by 2012. More rapid scale-up remains critically important.