Editor's note: Africa has the world's largest number of HIV infections and AIDS cases. Across the continent the disease is being battled with public education and antiretroviral drugs. A new additional strategy is male circumcision. Several tests show that circumcised men have substantially reduced risks of contracting HIV. In response, several campaigns have been launched to circumcise men.

GlobalPost has investigated this public health effort in eastern and southern Africa. The series starts in Kenya in the fishing villages by Lake Victoria and includes a video of a circumcision. Also, a Kenyan doctor describes his work running a circumcision clinic, health writer Mercedes Sayagues gives her controversial opinion on the issue and a South African doctor describes the circumcision campaign in several southern African countries.

WAKULA BEACH, Lake Victoria, Kenya — Mfangano Island on Lake Victoria, two hours by motorboat from mainland Kenya, is a popular destination spot for honeymooners on safari: a verdant fishing outpost without electricity or running water.

But this remote locale is the epicenter of Kenya’s AIDS crisis. And so, besides the honeymooners, this island also attracts NGO-workers armed with pamphlets and condoms and behavior-change slogans. The residents are used to the visitors. Samuel Gabari, a 23-year-old fisherman, answers my questions about his sexual habits as if reciting from a script.

“I only have one sexual partner,” he says. “And I always use condoms.”

The truth is more complicated. Sex here, like anywhere else, is often a mixture of business and pleasure. Gabari says fishermen can make $7-$25 a day, a kingly salary in this region. He’s constantly traveling from beach to beach, following the fish, sailing far from his girlfriend. At each beach there are temptations. “You have money, the women don’t have money, so they fall for you!” says Gabari. “That is part of the game!”

Even though everyone on this island seems to have memorized the catchphrases of AIDS prevention — “Abstinence, Be faithful, use Condoms” — those messages haven’t had much impact. About 21 percent of people on this island are infected with HIV, three times the national rate of 7 percent.

Now NGO-workers are offering fishermen like Gabari a new prevention tool: circumcision. The link between circumcision and reduced HIV susceptibility has been suspected since the mid-1980s, when AIDS researchers observed that circumcised Kenyan men who engaged with prostitutes were less likely to get infected. By 2007, three random clinical trials [GW1] in sub-Saharan Africa showed that circumcision reduced the risk of female-to-male HIV transmission by 50 to 60 percent.

The reason for the lower HIV infection rates for circumcised men is not fully understood. Some scientists say that the skin around the head of an uncircumcised penis is more porous. Others say that the moist environment under the foreskin invites bacterial infection, which, combined with poor hygiene, can induce lesions through which the virus can pass. Other researchers cite the large number of HIV-susceptible immune cells on the foreskin.

In 2007 the World Health Organization (WHO) recognized circumcision as a new AIDS prevention measure, opening the floodgates to American funding. That year, $16 million from the U.S. President's Emergency Plan for AIDS Relief (PEPFAR) went to circumcision programs in Africa, with $26 million in 2008. Higher numbers are likely on the way. Kenya’s campaign is the most ambitious at an estimated cost of $85 million over the next five years. Already, 50,000 Kenyans have been voluntarily circumcised, most of them fishermen. Researchers estimate that if we were to launch circumcision campaigns across the continent we could save 2.7 million lives over the next 20 years, or roughly the number of Africans who lose their lives to AIDS every 15 months.

Of course, long before male circumcision became the hot new weapon in the war on AIDS, it was an ancient rite of manhood practiced by many African tribes. Well over half of African men are circumcised in traditional ways. Generally performed on boys when they reach puberty, circumcision marks their readiness to take up the duties of men: to defend the village, find a wife and begin sexual activity.

In Kenya, in particular, circumcision is deeply tied up with male identity. The Luo tribe are the third largest ethnic group in Kenya, estimated to make up 13 percent of the country's 39 million people. The Luos do not traditionally circumcise.

In Kenya’s 2007 presidential election a Luo candidate began gaining strength in the polls, only to have some Kenyan newspapers mock his uncircumcised status, asking: How can a nation of men be led by a boy? These barbs go back to colonial times, when British authorities stoked cultural divisions to sow tribal enmity.

When circumcision was first introduced as a way to reduce HIV infections, the Luo Council of Elders balked. AIDS activists countered that circumcision was a medical intervention, not a cultural conversion. Luo parliamentarians joined the pro-circumcision bandwagon, testifying about their own positive experience under the knife. The tribal elders quickly bowed to political pressure from a community apparently ready to throw off tribal custom and join the modern world.

Along Lake Victoria, fishermen contemplating circumcision say that in addition to the health benefits, questions of manhood were very much on their minds. Fishermen said that circumcision had made them "perform better," feel more virile and last longer during sex.

“Some take drugs to have sex, but I just cut the foreskin,” said one 30-year-old fisherman, Julius Soba. “Circumcision is my stimulant!”

Local mobilizers trying to convert as many as possible to circumcision haven’t dissuaded them from this notion. More often they defer to existing cultural associations of circumcision with male potency and prowess. Women also got the message. A study in 2000 showed that 62 percent of Luo women said they preferred sex with a circumcised man. This was years before the pro-circumcision message was officially sanctioned. And since the Luo are uncircumcised, their preference was probably not based on direct experience.

“The truth is that sex is in the mind,” said Dishon Gogi, with the Nyanza Reproductive Health Society. Gogi criss-crosses Lake Victoria in a motorboat he calls the "circumcision boat," ferrying trained surgeons and supplies to the fishing communities. “If a man feels that he is stronger, he is stronger! If he feels he is a lion, he’s a lion! I only ask that they do it safely.”

Gogi’s boss, Dr. Kawango Agot, sounded a note of caution. If circumcision encourages people to have sex with more partners, or riskier sex, she noted, it will negate the benefits of circumcision and speed up the spread of AIDS. “That would be a disaster,” she said.

The genie is already out of the bottle. “It is demand driven!” says Dishon Gogi. He shows me the packed schedule of upcoming site visits for his circumcision boat. “Wherever we’re called we’ll answer. Like the Bible says, ‘wherever we’re called we’ll go.’”

More GlobalPost dispatches about male circumcision in Africa:

Video of circumcision, a Kenyan doctor gives his personal thoughts about circumcision, a South African doctor talks about the drive in southern African countries, a health specialist gives her controversial opinion about the male circumcision campaign.