Male circumcision, if widely adopted in Africa, would prevent 3 million deaths over 20 years. It would work as well as a moderately effective AIDS vaccine.

The prediction comes from an international team of researchers including Brian G. Williams, PhD, of the World Health Organization. They report their findings in the July issue of the public-access, online journal PLoS Medicine.

"Male circumcision could avert 2 million new HIV infections and 300,000 deaths over the next 10 years in sub-Saharan Africa," Williams and colleagues write. "In the 10 years after that, it could avert a further 3.7 million new infections and 2.7 million deaths."

About a fourth of the impact would be in South Africa, which is particularly hard-hit by the AIDS pandemic.

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These estimates are based on a 2005 clinical trial that found male circumcision reduces female-to-male spread of HIV -- the AIDS virus -- by 60 percent.

This would be the same effect as an AIDS vaccine that was 37 percent effective in protecting both men and women against HIV infection.

Preventing HIV infection of men would slow HIV spread to women. But Williams and colleagues note that women need protection of their own -- a safe, HIV-killing agent that could be applied directly to the vagina prior to sex.

And while it's important to find ways to cut the spread of HIV, it's even more important to get effective treatments to people already infected with the virus that causes AIDS.

"The need to keep HIV-positive people alive through the provision of [AIDS drugs] remains the most immediate priority," Williams and colleagues write.

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By Daniel J. DeNoon, reviewed by Louise Chang, MD

SOURCE: Williams, B.G. PLoS Medicine, July 2006; vol: 3 pp e262.