Mehta, S., Moses, S., Agot, K., et al. AIDS (November 2013), 27(18): 2899–2907, doi: 10.1097/01.aids.0000432444.30308.2d.
This article reported on a modeling study that accompanied long-term follow-up of the study population in the Kisumu medical male circumcision (MMC) clinical trial that ended in 2006. In this trial, MMC reduced HIV acquisition by 60 percent after approximately two years of follow-up. Men in the control group were offered circumcision, and participants in both arms followed for a total of 72 months. A modeling approach, marginal structural modeling, was used to estimate the efficacy of MMC while controlling for confounding and bias, thereby increasing confidence that any reduction in HIV incidence was due to MMC. MMC's efficacy against HIV acquisition was sustained at 58 percent over six years. These findings were from a long-term cohort that received risk reduction counseling and testing and treatment for sexually transmitted infections every six months, which may limit their generalizability. The authors suggested that the finding of sustained efficacy, consistent with the results from the three randomized efficacy trials, supports the World Health Organization recommendation to scale up MMC to reduce HIV.