Alsallaq, R.A., J.M. Baeten, C.L. Celum, et al. PLoS One (January 2013), Vol. 8 No. 1, pp. e54575.
The authors applied a mathematical model to assess the potential effect of an HIV combination intervention on HIV incidence in KwaZulu-Natal, South Africa. The combination intervention included high HIV testing coverage every four years, risk behavior reduction following diagnosis, antiretroviral therapy (ART) initiation at CD4 count of ≤350 cells/ml, and medical male circumcision. The authors analyzed individual components and then combined components to estimate population-level impact; explored the effect of expanding ART to all persons testing positive; assessed factors that determined impact; and measured the short- and long-term effect of the combined components. The combination intervention showed major reductions in HIV incidence-nearly 50 percent in four years and 60 percent after 25 years. The combined components had synergistic effects. ART had the greatest individual effect, reducing incidence by 33 percent. Expanding ART to all persons diagnosed HIV positive could reduce incidence by 63 percent at four years, and by 76 percent after 15 years. Uptake of testing and risk behavior reduction had the greatest short-term impact; periodic testing and ART retention had the greatest long-term impact. The full impact of combination prevention could be achieved in 10-15 years. The authors concluded that reducing HIV incidence is feasible in high-prevalence settings with combination interventions implemented at high coverage and with robust evaluation to assess population-level impact.