In September, 2016, South Africa adopted a policy of providing antiretroviral treatment to everyone infected with HIV irrespective of their CD4 cell count. Studies of universal treatment and expanded prevention of HIV differ widely in their projections of effects and the associated costs, so we did this analysis to attempt to find a consensus. We used data on HIV from the Joint UN Programme on HIV and AIDS (UNAIDS) from 1988 to 2013 and from data from WHO on tuberculosis from 1980
to 2013 to fit a dynamical model to time trends in HIV prevalence, antiretroviral therapy (ART) coverage, and tuberculosis notification rates in South Africa. We then used the model to estimate current trends and project future patterns in HIV prevalence and incidence, AIDS-related mortality, and tuberculosis notification rates, and we used data from the South African National AIDS Council to assess current and future costs under different combinations of treatment and prevention approaches. We considered two treatment strategies: the Constant Effort strategy, in which people infected with HIV continue to start treatment at the rate in 2016, and the Expanded Treatment and Prevention (ETP) strategy, in which testing rates
are increased, treatment is started immediately after HIV is detected, and prevention programmes are expanded.