Male circumcision shows promise as defense against HIV transmission

Two major studies of male circumcision in Africa have found that the simple surgical procedure reduces the risk of HIV infection by half -- a hugely important result that is likely to prompt many African nations hard hit by AIDS to promote it as a means to control the epidemic.

The separate studies in Kenya and Uganda were financed by the National Institutes of Health and compared HIV infection rates between groups of circumcised and uncircumcised men and teenage boys.

On Tuesday, an NIH safety panel examined interim results and found that the uncircumcised men in both studies were becoming infected at twice the rate of the men who had the procedure. The panel concluded it would be unethical to allow the experiments to continue until mid-2007 as planned without offering the surgery to the uncircumcised group.

The results are consistent with a similar clinical trial halted in South Africa last year after French researchers found that circumcision -- the surgical removal of foreskin from the penis -- offered a 60 percent protection rate.

"These results demonstrate that adult male circumcision, when performed by a trained medical provider, is both safe and effective at reducing the risk of HIV infection,'' Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said during a telephone news conference.

Fauci stressed that circumcision is one more tool available to fight HIV and should not be considered a replacement for other measures such as the use of condoms. "These results could be negated by a small decrease in condom use or the addition of more sexual partners,'' he warned.

AIDS prevention experts around the globe have been anxiously awaiting the interim results of the two trials after an early peek at the data in June led the NIH panel to order the studies to continue. The three African trials together were designed to offer definitive proof that male circumcision helped prevent HIV infection. Dozens of studies conducted since the 1980s found similar results but lacked the scientific rigor of a randomized clinical trial.

"This is not a magic bullet but a potentially important intervention,'' said Dr. Kevin De Cock, director of HIV/AIDS programs for the World Health Organization.

He said the agency will meet early next year to consider how African nations can safely offer the procedure on a massive scale. Adult male circumcision can cost anywhere from $25 to $500 in Africa, and De Cock said it will be impossible for African countries to provide without substantial foreign assistance.

Dr. Bertran Auvert, the French researcher who conducted the earlier South African study, has reported that widespread adoption of male circumcision could avert 2 million HIV infections.

Reached in South Africa, he said the Kenyan and Uganda studies are consistent with his findings. "We now need to find ways to reduce the price of male circumcision and make it affordable. This is not yet the case,'' he said.

Doctors theorize that circumcision might protect against HIV infection because the foreskin is rich in a type of white blood cell that is a favorite target of the AIDS virus. In addition, some studies suggest that circumcised males are less likely to have other sexually transmitted diseases, which cause sores that serve as gateways for HIV to enter the bloodstream.

"This is a landmark day in the history of fighting this epidemic,'' said Robert Bailey of the University of Illinois at Chicago, who led the study in Kisumu, a city in western Kenya where the prominent tribe, the Luo, do not practice male circumcision.

A medical anthropologist, Bailey first became interested in circumcision for AIDS prevention in 1985, when colleagues in the field began noticing that HIV rates were much higher in regions of Africa populated by non-circumcising cultures. He suspected the higher rates partly explained why circumcising cultures in West Africa had HIV infection rates below 5 percent, while close to one-third of the adult male population eventually was infected in Botswana, Zimbabwe and the KwaZulu-Natal province of South Africa.

In 1999, Bailey and UCSF researcher Daniel Halperin published a commentary in the British medical journal The Lancet challenging the public health community to take seriously dozens of studies showing that circumcision appeared to offer some protection against HIV.

That challenge ultimately led to NIH funding for the two clinical trials.

Halperin, now a researcher at the Harvard School of Public Health, said from Zimbabwe on Wednesday that he will crack open a bottle of Champagne to celebrate the study results. "Only a couple of years ago, people would laugh and make jokes about this. We've come a long way,'' he said. "Circumcision is now the only intervention for the prevention of HIV that has passed the highest standard for clinical trials. I think it's a pretty historical event.''

As a result of publicity about various circumcision trials, there is a 9-month waiting list for the procedure at public hospitals in Swaziland, where until recently Halperin was posted as a researcher for USAID.

Bailey's Kisumu study enrolled 2,784 HIV-negative men ages 18-24 beginning in 2005. It found a 53 percent reduction in HIV transmission among those who were circumcised. By the time the trial was stopped, 87 percent of participants had been followed for the two-year enlistment period.

The second study, led by Johns Hopkins University epidemiologist Dr. Ronald Gray, enrolled 4,996 HIV-negative men ages 15-49 in the rural Rakai district of Uganda, and the interim results showed a 48 percent protective effect in the circumcised group.

Despite the study results, circumcision remains a controversial medical procedure that critics consider genital mutilation. Anti-circumcision activist Marilyn Milos, a nurse who is executive director of NOCIRC in San Anselmo, said that while the trial results were interesting, "anybody who believes that circumcision will protect them from HIV is obviously making a deadly mistake.''

She contends that circumcision removes "the most erogenous tissue" of the male body and that the diminished sensitivity she said circumcised men experience is a further disincentive to use condoms. Consistent condom use, she said, remains the only proven method of preventing HIV, and programs that promote their use have reversed infection rates in Thailand, Senegal and Uganda.

"My greatest fear is that they will begin to circumcise more and more people in Africa and ultimately find out it was not effective,'' she said.

Mitchell Warren, executive director of the AIDS Vaccine Advocacy Coalition, hailed the results of the three trials but warned that it is critical that any expansion of the procedure must ensure its safety.

"Male circumcision is a surgical procedure. It requires trained personnel, sterile instruments, and adequate supplies of items like gauze and bandages," he said. "In the developing world, these resources are often in short supply, and, in their absence, the procedure can lead to infections and even death.''

Meanwhile, researchers will continue to follow the health of the participants in the African circumcision trials. A fourth study, underwritten in Uganda by the Bill & Melinda Gates Foundation, will attempt to determine whether women also benefit from the reduced HIV infection risk in a population of circumcised men.