Significant reduction in HIV prevalence according to male circumcision intervention in sub-Saharan Africa.

BACKGROUND Observations that reduced adult HIV prevalence in sub-Saharan Africa correlated with levels of male circumcision (MC), have suggested that MC could be used as a preventative measure against HIV infection. The exact benefits of this intervention are uncertain. Moreover if MC is not feasible for the whole male population, which groups should be targeted? METHODS A mathematical model simulated observed levels of HIV prevalence under the complete range of current levels of circumcision. Increased MC from 2007 was incorporated in this model and used to simulate HIV prevalence in 2020. RESULTS Complete coverage by MC could reduce HIV prevalence from 12 to 6% for an average population country in sub-Saharan Africa in 2020. This reduction is scaled proportionally when lower circumcision levels are achieved. These benefits are achieved mostly by circumcising men between 20 and 30 years of age (adult prevalence reduced from 12 to 10%), and those with riskier behaviour (8 to 6.9%). Complete negation of these benefits requires at least 40% of circumcised males to significantly increase risky behaviour. CONCLUSIONS MC provides an effective intervention in sub-Saharan Africa to reduce HIV prevalence. It is most effective when applied to 20-30 year old risky males with diminishing returns with application to the wider male population.