Circumcision and HIV


Male circumcision reduces the risk of HIV transmission from women to men. In 2011, the World Health Organization and the Joint United Nations Programme on HIV/AIDS stated that male circumcision is an efficacious intervention for HIV prevention if carried out by medical professionals under safe conditions. The United States Centers for Disease Control and Prevention states that circumcision reduces the risk that a man will acquire HIV and other sexually transmitted infections from an infected female partner.
A 2019 meta-analysis of men who have sex with men found circumcision was associated with a 42% reduction in the odds of HIV in low and middle income countries, but not in high income countries. The CDC previously stated "There are as yet no convincing data to help determine whether male circumcision will have any effect on HIV risk for men who engage in anal sex with either a female or male partner, as either the insertive or receptive partner."

Recommendations

In 2007, the WHO reviewed the totality of evidence concerning male circumcision and HIV, and issued the following joint recommendations with UNAIDS.
Kim Dickson, coordinator of the working group that authored the report, commented:
The World Health Organization said: "Although these results demonstrate that male circumcision reduces the risk of men becoming infected with HIV, the UN agencies emphasize that it does not provide complete protection against HIV infection. Circumcised men can still become infected with the virus and, if HIV-positive, can infect their sexual partners. Male circumcision should never replace other known effective prevention methods and should always be considered as part of a comprehensive prevention package, which includes correct and consistent use of male or female condoms, reduction in the number of sexual partners, delaying the onset of sexual relations, and HIV testing and counselling."

Men who have sex with men

A 2008 meta-analysis of gay and bisexual men found that the rate of HIV infection was not lower among men who were circumcised. For men who engaged primarily in insertive anal sex, no effect was observed. Observational studies included in the meta-analysis that were conducted prior to the introduction of highly active antiretroviral therapy in 1996 demonstrated a protective effect for circumcised MSM against HIV infection.
A 2017 and 2011 review found some evidence that circumcision was protective in MSM.

Programs

In 2011, UNAIDS prioritized 14 high HIV prevalence countries in eastern and southern Africa, with a goal of circumcising 80% of men by the end of 2016. In parallel, WHO developed a Framework for evaluating new, simpler circumcision techniques, which gave impetus to the development of two new devices that are currently being scaled-up in the 14 high HIV prevalence countries. Overall, 14.5 million males were circumcised as of the end of 2016.
UNAIDS' Fast-Track Plan for ending the AIDS Epidemic by 2030 calls for an additional 25 million circumcisions in these high-priority countries by 2020, which will require to 5 million procedures per year, nearly double the current rate. To reach this goal, UNAIDS is counting on advances in circumcision techniques.
Newly circumcised men must refrain from sexual activity until the wounds are fully healed. Some circumcised men might have a false sense of security that could lead to increased risky sexual behavior.

Mechanism of action

Experimental evidence supports the theory that Langerhans cells in foreskin may be a source of entry for the HIV virus. Excising the foreskin removes a main entry point for the HIV virus.

History

Hypotheses and epidemiologic studies

Valiere Alcena, in a 1986 letter to the New York State Journal of Medicine, noted that low rates of circumcision in parts of Africa had been linked to the high rate of HIV infection. Aaron J. Fink several months later also proposed that circumcision could have a preventive role when the New England Journal of Medicine published his letter, "A possible explanation for heterosexual male infection with AIDS," in October, 1986. Alcena later said that Fink had expropriated his ideas.
By 2000, over 40 epidemiological studies had been conducted to investigate the relationship between circumcision and HIV infection. A meta-analysis conducted by researchers at the London School of Hygiene & Tropical Medicine examined 27 studies of circumcision and HIV in sub-Saharan Africa and concluded that these showed circumcision to be "associated with a significantly reduced risk of HIV infection" that could form part of a useful public health strategy.
A 2005 review of 37 observational studies expressed reservations about the conclusion because of possible confounding factors, since they were all observational studies. The authors stated that three randomized controlled trials then underway in Africa would provide "essential evidence" about the effects of circumcision on preventing HIV.

Randomized controlled trials in Africa

Three randomized controlled trials took place in South Africa, Kenya and Uganda. Southern and eastern Africa has the highest rate of adult HIV infection in the world.
The first trial to publish, in 2005, was that from South Africa, named ANRS-1265 or the "Orange Farm trial". After 18 months, there were 20 HIV infections in the intervention group and 49 in the control group, a finding which led to suspension of the trial on ethical grounds. The other two African trials were also halted on ethical grounds, again because those in the circumcised group had a lower rate of new HIV infections than the control group.
The Orange Farm trial report concluded that circumcision offered protection against HIV infection "equivalent to what a vaccine of high efficacy would have achieved".
A 2009 systematic review from the Cochrane Collaboration included these 3 randomized controlled trials. It provided strong evidence that medical male circumcision reduces the acquisition of HIV by heterosexual men by about 60%, while adverse events are rare, and recommended inclusion of male circumcision into current HIV prevention guidelines. Sites for these studies were chosen specifically because of the high rates of HIV in those geographic areas.
The methodology of the original studies which were the subject of a meta-analysis was severely criticized: "Our results clearly show that these African CRFs were methodologically flawed from start to finish... From the start, there was almost nothing correct with these studies. It was quite clear that these studies were unethical. They would never have been approved by a single ethics committee in the United States.", as stated by George Hill.

Society and culture

The prevalence of circumcision varies across Africa. Studies were conducted to assess the acceptability of promoting circumcision; in 2007, country consultations and planning to scale up male circumcision programmes took place in Botswana, Eswatini, Kenya, Lesotho, Malawi, Mozambique, Namibia, Rwanda, South Africa, Uganda, Tanzania, Zambia and Zimbabwe.
The UNAIDS/WHO/SACEMA Expert Group on Modelling the Impact and Cost of Male Circumcision for HIV Prevention found "large benefits" of circumcision in settings with high HIV prevalence and low circumcision prevalence. The Group estimated "one HIV infection being averted for every five to 15 male circumcisions performed, and costs to avert one HIV infection ranging from US$150 to US$900 using a 10-y time horizon". The World Health Organisation states that circumcision is "highly cost-effective" in comparison to other HIV interventions when data from the South African trial are used, but less cost-effective when data from the Ugandan trial are used.