AIDS Alert International

Body of research grows in support of male circumcision for HIV prevention

Studies have no trouble enrolling volunteers

With the weight of two clinical trials in Uganda and Kenya showing that male circumcision can reduce HIV risk by about 60 percent, the World Health Organization (WHO) of Geneva, Switzerland, is evaluating the evidence in preparation for a possible public health recommendation and/or course of action.

One of the latest studies showing the potential for circumcision to prevent HIV infection involved a randomized controlled trial of 2,784 men, ages 18-24 years, in Kisumu, Kenya.1

The trial had been stopped early on Dec. 12, 2006, by a data and safety monitoring board (DSMB), and follow-up was incomplete for 240 participants, after 47 men in the control group and 22 in the intervention group tested positive for HIV.1

The 2-year HIV incidence in the circumcision group was 2.1 percent, while the 2-year HIV incidence in the control group was 4.2 percent.1

Investigators concluded that the protective effect of circumcision was 60 percent.1

Now that the recent studies have supported an earlier study about the preventive value of circumcision, it's time to work with ministries of health in Eastern and Southern Africa to assist them in formulating policies that integrate existing circumcision with HIV measures in place for their communities, suggests Robert C. Bailey, PhD, MPH, a professor of epidemiology in the School of Public Health at the University of Illinois at Chicago. Bailey was the principal investigator of the Kenyan circumcision study.

"We don't want circumcision to be a stand-alone intervention, but rather a full package of services that will address the HIV epidemic in different communities," Bailey says. "So it's going to be a collaborative effort by researchers, the international community, donor communities, and the government ministries of health in the impacted countries."

The Lancet, which published the Kenyan and Ugandan circumcision studies in February 2007, noted in an editorial that the studies' publication signals a new era for HIV prevention.2

Nonetheless, the editorial cautions that no single prevention action will halt the epidemic, and more interventions that are in the control of women are needed.2

Circumcision alone may not stop the epidemic, but it will prevent many infections, particularly in parts of sub-Saharan Africa, Bailey says.

In another recent modeling study, investigators concluded that male circumcision could prevent two million new HIV infections over the next 10 years and save at least 300,000 lives in that same period.3

In South Africa, alone, male circumcision could reduce HIV incidence by about 173,610 infections per year.3 (See chart from study.)

"Certainly in areas where HIV prevalence is high and most men are not circumcised, it's really the only proven HIV prevention strategy for adults," Bailey says. "We now have three trials all with consistent results, and there is no more compelling evidence for any measure we have for preventing HIV infection in adults."

Many studies have looked at the various other aspects of male circumcision as a prevention method, and most of these published findings have been positive as well.

For example, a study that examined whether circumcised men engaged in riskier sexual behavior post-circumcision concluded that this did not occur within the first year after they were circumcised.4

At each visit with men participating in the circumcision trials, there was a risk assessment, followed by risk counseling, and a risk reduction plan, says Kawango Agot, PhD, MPH, director of the Impact Research and Development Organization of Kisumu, Kenya.

"Clients chose what was likely to work for them among the different safe sex options," Agot says. "At the next visit the counselor would review the risk reduction plan to see if it worked or not, and, if not, the client would either choose to continue with the same strategy or chose a different one."

The process was the same for both the circumcised and uncircumcised men, and investigators found no difference in the men's reports of risky sex acts per week, number of risky sex partners, and condom use.4

"We asked structured questions about whether they had used a condom with each of the partners and at each of the sex acts," Agot says. "We also asked questions about penile trauma during sex, such as bleeding, sores, cuts, abrasions."

Circumcision is very rare in the regions in which men were recruited for the circumcision trials, Agot notes.

"In Kenya, if circumcision is done for cultural reasons, it's done by a whole ethnic community as a rite of passage from childhood to adulthood," Agot says.

The clinical trials took place in districts inhabited by the Luo, a large ethnic community in Kenya, that does not traditionally practice circumcision, Agot adds.

Despite this ethnic community's traditions, the trials had no difficulty recruiting men for the circumcision study, and even had more who wanted the procedure done than were needed, Agot says.

Finding men to voluntarily become circumcised does not appear to be a problem, according to recent studies, and neither does the public health cost of the procedure, at least one study shows.

Investigators found that full coverage of the male circumcision intervention in a region with high HIV prevalence could save millions of dollars.5

The expected cost of a circumcision program would be $181, says James G. Kahn, MD, MPH, professor of health policy and epidemiology at the Institute for Health Policy Studies at the University of California, San Francisco. Kahn was the principal investigator of the cost-effectiveness study.

The total savings derived from the circumcision intervention's ability to prevent HIV, calculated over a lifetime for 1,000 men, would be $2.4 million.5

"All of this is adjusted in today's dollars," Kahn says.

Other new research found that male circumcision is very strongly associated with lower cervical cancer rates and HIV infection, says Paul Drain, MPH, MD-candidate, an investigator at the University of Washington in Seattle, WA.

Drain was the lead investigator in an ecologic analysis of 118 developing countries that had various ranges of male circumcision rates. The study compared HIV prevalence, cervical cancer incidence, and the incidence of other diseases, including tuberculosis, malaria, hepatitis C, syphilis, and HSV-2 with circumcision rates.6

"Where circumcision would have the biggest impact is in sub-Saharan Africa, depending on which countries many of the males are uncircumcised," Drain says.

A recent study that reviewed recent literature on circumcision and its impact on HIV transmission suggests that male circumcision should be considered as a potential public health prevention tool that will need to be carefully scaled up and integrated into other prevention programs.7

"The data on male circumcision effectiveness is the best quality data we have on prevention," Kahn says. "All of the studies show the same effect size, and the quality of evidence is unheard of in anything except giving nevirapine to HIV-infected pregnant women, and circumcision is one of the few prevention strategies that are permanent."

Getting men to wear condoms can work, but it requires prevention programs that work with their sexual partners to make certain the condom-wearing behavior persists, Kahn adds.


  1. Bailey RC, Moses S, Parker CB, et al. Male circumcision for HIV prevention in young men in Kisumu, Kenya: a randomised controlled trial. The Lancet. 2007;369:643-656.
  2. Newer approaches to HIV prevention (Editorial). The Lancet. 2007;369:615.
  3. Williams BG, Lloyd-Smith JO, Gouws E, et al. The potential impact of male circumcision on HIV in sub-Saharan Africa. PLOS Med. 2006;3(7):1032-1040. Online at
  4. Agot KE, Kiarie JN, Nguyen HQ, et al. Male circumcision in Siaya and Bondo Districts, Kenya: prospective cohort study to assess behavioral disinhibition following circumcision. J Acquir Immun Defic Syndr. 2007;44(1):66-70.
  5. Kahn JG, Marseille E, Auvert B. Cost-effectiveness of male circumcision for HIV prevention in a South African setting. PLOS Medicine. 2006;3(12). Online at
  6. Drain PK, Halperin DT, Hughes JP, et al. Male circumcision, religion, and infectious diseases: an ecologic analysis of 118 developing countries. BMC Infect Dis. 2006;6:172.
  7. Quinn TC. Circumcision and HIV transmission. Curr Opin Infect Dis. 2007;20(1):33-38.