Circumcision
At the last IAS conference in 2005, the first major study showing that circumcision reduced the risk of HIV infection for men was presented. Since then two more studies have shown very similar results: circumcision reduces the risk of HIV infection in men by around 60%.

As a result, the World Health Organization and UNAIDS have recommended that HIV prevention programmes should offer medical circumcision to men.

But there are still lots of unanswered questions about circumcision as an HIV prevention strategy.

One concern is the safety of circumcision: how often do men experience complications as a result of circumcision, and how long does it take for wounds to heal?

A study analysing complication rates in two groups, HIV-negative men and HIV-positive men with CD4 cell counts above 350, found a similar rate of complications, around 3%, in both groups. But HIV-positive men were less likely to have complete wound healing after one month. Almost 30% still had unhealed wounds from the surgery, compared with 20% of HIV-negative men.

The study was criticised by Kevin de Cock of the World Health Organization because it didn’t include men with lower CD4 cell counts, who might have a higher risk of infections after surgery.

The protective effect of circumcision among men who have sex with men is still unknown too. Although men in Latin America, where circumcision is rare, seem willing to take part in a trial of its effectiveness, a study from Australia questioned whether it has any protective effect for this group.

Looking at all the new infections among men who have sex with men, since 2000, researchers found no difference between circumcised and uncircumcised men in their risk of HIV infection.

Another unanswered question is the cost. A modelling study presented today suggests that mass circumcision programmes in African countries severely affected might cost governments and international donors $500 million over the next five years. But by preventing infections they have the potential to save $3 - $4 billion in antiretroviral treatment costs over the next 20 years