Analysis indicates men who are circumcised have about half the risk
of acquiring HIV infection of men who are uncircumcised
After an interim analysis indicated that men who are circumcised have about half the risk of acquiring HIV infection through vaginal intercourse as do men who are uncircumcised, the National Institutes of Health decided to stop two trials underway in Uganda and Kenya prior to their completion. The announcement came during a news conference on Dec. 13.
Officials said the findings were not surprising since researchers have known for many years that rates of HIV infection in Africa generally are lower among populations where most of the men are circumcised. However, because most of the men who are circumcised are Muslim, they did not know whether it was because of the circumcision or because of other social or cultural practices associated with that religion.
The trials enrolled volunteers who wanted to be circumcised and randomized them to receive the procedure immediately or after two years. All participants were educated on safer sex practices and the use of condoms.
The first randomized controlled trial to test circumcision as a prevention intervention was carried out in South Africa, and was stopped in 2005 when interim analysis found that it reduced female-to-male transmission of HIV by at least 60 percent. Those results were so dramatic that it would have been unethical to delay circumcision for those volunteers who had been randomized to receive it at the conclusion of the trial, officials said. Additional trials on circumcision were underway in Uganda and Kenya and were allowed to continue with periodic monitoring of the results by a data safety monitoring board. In December, the board determined that there was a reduction in risk of acquiring HIV of 48 percent and 53 percent respectively and advised that the trials be terminated early.
“These results indicate that adult male circumcision could be an important addition to an HIV prevention strategy for men,” said Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases at NIH. “However, it is not completely protective and must be seen as a powerful addition to, not a replacement for, other HIV prevention methods.”
Fauci explained that circumcision provides protection by removing the foreskin, which contains cells that are particularly vulnerable to HIV. The procedure also changes the physical characteristics of the head of the penis from that of a mucosal membrane, which the virus can easily enter, to a harder “kernatinized” surface that is more difficult to penetrate, he said.
The World Health Organization (WHO) began to develop activities around male circumcision after results of the South African trial became known last year, said Kevin De Cock, director of WHO’s department of HIV/AIDS. The organization will offer guidance and training to countries that choose to make circumcision more widely available.
“This has the potential to prevent many tens of thousands, perhaps even millions of infections over the coming years,” De Cock said.
However, he warned that circumcision must be carried out under proper medical conditions. There is risk of common infection with any medical procedure, and improperly sterilized tools carry the added risk of HIV infection.
Circumcision is common in the United States, reaching a peak of about 85 percent of males born in 1965 but declining thereafter. Part of the decline is because medical associations decided that the procedure carries no medical benefit and have dropped their support for it. As a result some insurance providers no longer provide reimbursement.
Statistics show that whites are more likely to be circumcised than are people of color in the U.S., suggesting a possible reason why, given the recent evidence of the protective effect of circumcision from the trials in Africa, rates of HIV infection are higher among African-Americans and Hispanics than whites.
This article appeared in the Dallas Voice print edition, December 22, 2006.