Smith, J.A., Anderson, S-J., Harris, K., et al. The Lancet HIV (June 2016), 3(7): e289–296, doi: 10.1016/S2352-3018(16)30036-4.
To identify optimum resource allocations, the authors of this study developed a model of the HIV epidemic in South Africa that simulated the cost and effects of a wide portfolio of options for HIV prevention. The model incorporated current interventions (including condoms, antiretroviral therapy, and pre-exposure prophylaxis or PrEP) and potential interventions to be added in the short or long term (vaginal rings and broadly neutralizing HIV-1 antibodies, or bNAbs). For each intervention, the authors defined coverage levels for seven population subgroups (female sex workers aged 15–49 years and high- and low-risk men and women in various age categories). All interventions had the potential to reduce HIV incidence substantially from 2016–2050. Vaccination showed the largest potential impact when scaled up to maximum coverage, followed by long-acting antiretroviral drugs, oral PrEP, bNAbs, and condoms. The mix of current and future interventions that showed the highest potential included scale-up of male circumcision and early ART initiation with outreach testing (which are available immediately and are low-cost and highly efficacious); intravaginal rings targeted to sex workers; and vaccines which can achieve a large effect if scaled up even if imperfectly efficacious). The authors concluded that scaling up existing interventions and developing a successful vaccine would have the greatest long-term impact on the epidemic.