Male Circumcision Reduces HIV Risk by 60 Percent, Says Study
The Guardian (London) (10.25.05): Ian Sample
In a recently published study tracking more than 3,000 heterosexual men for almost two years, scientists have found that circumcision reduces a man's risk of acquiring HIV by 60 percent. Researchers who previously noted differences in HIV acquisition between groups of circumcised and uncircumcised men have suspected the procedure might offer some protection against the virus, but no large-scale studies had been carried out to investigate the effect.
Dr. Adrian Puren, of the National Institute for Communicable Diseases in Johannesburg, and researchers in Paris recruited 3,274 South African volunteers, ages 18-24, who were considering circumcision. Half the subjects underwent the operation. Both groups were monitored for HIV infection for 21 months. Of those who had been circumcised, 20 became HIV-infected, while 49 of the uncircumcised group did so. The difference was so significant the study was halted on ethical grounds. The procedure's protective effect appears to be "equivalent to what a vaccine of high efficacy would have achieved," the authors wrote.
While this effect is not well understood, scientists know that the part of the foreskin removed during the operation is rich in Langerhans cells to which HIV attaches. "HIV has to gain access to the body and to do that it binds to particular cell types," Puren said. "By removing the skin that contains those cells, you remove the tissue the virus would normally bind to."
However, experts were quick to point out the limitations of this knowledge. "Circumcision is not going to prevent HIV infection in the long run," said Peter Cleaton-Jones, chairperson of the human research ethics committee at the University of Witwatersand in Johannesburg. "If circumcised men think they're protected against HIV, they're fooling themselves. If they don't practice safe sex, they'll still be at risk, it's just a lower risk."
In addition, Will Nutland of the Terrence Higgins Trust noted that circumcision would have little effect in the United Kingdom, where most new HIV cases are homosexual men infected through receptive anal sex.
Similar trials in Kenya and Uganda are expected to end in the coming year.
The full report, "Randomized, Controlled Intervention Trial of Male Circumcision for Reduction of HIV Infection Risk: The ANRS 1265 Trial," was published in the Public Library of Science Medicine (2005;2(11):e298).
S. Alex Williams