Londish Gregory J, Murray John M
School of Mathematics and Statistics, University of New South Wales, Sydney 2052 NSW, Australia.
Int J Epidemiol. 2008 Dec;37(6):1246-53. doi: 10.1093/ije/dyn038. Epub 2008 Mar 3.
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?
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.
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.
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.
撒哈拉以南非洲地区成人艾滋病毒流行率的下降与男性包皮环切术（MC）水平相关，这表明MC可作为预防艾滋病毒感染的一项措施。这种干预的确切益处尚不确定。此外，如果MC对全体男性人口不可行，那么应针对哪些人群？
一个数学模型模拟了当前包皮环切术水平范围内观察到的艾滋病毒流行率。将2007年以来增加的MC纳入该模型，并用于模拟2020年的艾滋病毒流行率。
到2020年，对于撒哈拉以南非洲的一个平均人口国家，MC全覆盖可将艾滋病毒流行率从12%降至6%。当包皮环切术水平较低时，这种下降按比例缩放。这些益处主要通过对20至30岁男性进行包皮环切术实现（成人流行率从12%降至10%），以及对行为风险较高者进行包皮环切术（从8%降至6.9%）。要完全抵消这些益处，至少需要40%接受包皮环切术的男性显著增加危险行为。
在撒哈拉以南非洲，MC是一项降低艾滋病毒流行率的有效干预措施。应用于20至30岁有风险的男性时最为有效，而应用于更广泛男性人群时效果递减。
