A recent review of 32 studies from eight countries has revealed that men who are uncut (uncircumcised) are two to eight times more likely to be infected with the human immunodeficiency virus (HIV), and in regions where circumcision is widespread, there appears to be a direct correlation with lower HIV infection rates.

Although the new report primarily surveys heterosexual men in developing countries, at least three large surveys of American men who have sex with men have reached nearly as alarming conclusions: gay and bisexual men with intact foreskins are at least twice as likely to be HIV-positive as men who are circumcised.

Biological and epidemiological evidence linking male circumcision with the virus that causes AIDS has been widely known among researchers for years. Yet policy-makers and educators have failed to direct adequate resources to inform people with the potentially life-saving information, according to the report entitled "Male Circumcision and HIV Infection: 10 Years and Counting," published in this month's issue of the Lancet, a prestigious medical journal.

"The number of infections probably caused by lack of male circumcision already reaches into the millions," said the study's lead author, Daniel Halperin, Ph.D., an assistant adjunct professor of community health systems and medical anthropology at University of California at San Francisco (UCSF). "We would expect the international health community to at least consider some form of action, but male circumcision remains largely unexplored as a tool against AIDS."

Heterosexual HIV transmission is much more common in Africa and South and Southeast Asia than in the United States, and epidemiologists have observed a statistically significant link between infection rates and prevalence of male circumcision in these regions, which by far represent the greatest proportion of AIDS cases worldwide.

In West African countries, where circumcision in infancy is common, only 1 to 5 percent of the population is HIV-positive, while nearly a quarter of people in the predominately non-circumcising Eastern and Southern African nations are infected.

Scientists point to several factors that make men with uncut penises more prone to HIV infection.

"The foreskin is sort of an Achilles' heel that allows a man to be infected from a vagina or anus," Halperin told the Bay Area Reporter. "It's fragile tissue -- it can get torn during intercourse, and is also more susceptible to sexually transmitted diseases." Additionally, there is a higher concentration in the penile foreskin of immune system cells known as Langerhans cells than is found in the cervix, vagina or rectum; Langerhans cells are particularly vulnerable to HIV infection.

Other researchers have previously reported that "tops" -- gay and bisexual men who are exclusively the insertive anal sexual partner -- are significantly less likely to be infected with HIV than there receptive "bottom" partner.

But Halperin told the B.A.R. that uncut tops are more likely to be infected through contact with their partner's rectal lining, and should consider themselves at greater risk -- especially if a condom is not always used.

"If I were a top, and I didn't like to use condoms, I would consider getting circumcised," Halperin said. "If that person is not going to use a condom, maybe we'd all be better off if that person was circumcised." Halperin strongly emphasized that circumcision should never be considered an alternative to using condoms.

Prevailing attitudes against adult circumcision, shared by the vast majority of males throughout the world, are often attributed to religious, cultural, or sexual beliefs.

For new parents in the United States and other Western countries, the anti-circumcision bias does not always extend to their infant boys. The federal Department of Health and Human Services has reported that in recent years, about 60 percent of babies with penises are circumcised annually.

Among many gay and bisexual men in the United States, uncut penises are a highly coveted delicacy, and uncut men of all sexual orientations will often claim heightened sexual gratification due to their foreskins. Halperin acknowledged that there likely will be little movement among adult men, especially gay and bisexual men, to have their foreskins surgically removed.

"There's a huge anti-circumcision movement, particularly in the Bay Area. It's a politically charged issue," Halperin said.

Indeed, Bay Area educators targeting gay and bisexual men with safer sex information have not focused on circumcision as a means of HIV prevention.

Tim Teeter, a treatment support specialist with the San Francisco AIDS Foundation, also does not foresee a foreskin removal fad in the gay male community, despite the increased risk of HIV infection. "Most guys who are uncircumcised are really proud of the fact that they are uncircumcised," he told the B.A.R. "So it's not a simple matter, to say 'just get circumcised.'"

Teeter suggested that tops consider using condoms, "a much less painful option."