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December 13, 2006

Studies Show Adult Male Circumcision Reduces Acquisition of HIV

Clinical Trials Stopped Early After Positive Results Found

The National Institute of Allergy and Infectious Diseases (NIAID) announced an early end to two clinical trials because an interim review of trial data revealed that medically performed circumcision significantly reduces a man’s risk of acquiring HIV through heterosexual intercourse. Researchers at the Johns Hopkins Bloomberg School of Public Health led the Rakai, Uganda, trial, which showed a 48 percent reduction in HIV acquisition in circumcised men relative to uncircumcised men. The other trial performed in Kisumu, Kenya, by researchers from the University of Illinois, Chicago, and the University of Manitoba, Canada, found a 53 percent reduction of HIV acquisition in circumcised men.

In a statement, National Institutes of Health director Elias A. Zerhouni, MD, said, “These findings are of great interest to public health policy makers who are developing and implementing comprehensive HIV prevention programs. Male circumcision performed safely in a medical environment complements other HIV prevention strategies and could lessen the burden of HIV/AIDS, especially in countries in sub-Saharan Africa where, according to the 2006 estimates from UNAIDS, 2.8 million new infections occurred in a single year.”

“Many studies have suggested that male circumcision plays a role in protecting against HIV acquisition,” said NIAID Director Anthony S. Fauci, MD. “We now have confirmation--from large, carefully controlled, randomized clinical trials--showing definitively that medically performed circumcision can significantly lower the risk of adult males contracting HIV through heterosexual intercourse. While the initial benefit will be fewer HIV infections in men, ultimately adult male circumcision could lead to fewer infections in women in those areas of the world where HIV is spread primarily through heterosexual intercourse.”

The researchers stressed that circumcision was not an absolute protection against HIV and is only part of a broader HIV prevention strategy that includes limiting the number of sexual partners and using condoms during intercourse.

The Ugandan trial was led by Ronald Gray, MBBS, MSc, and Maria Wawer, professors in the Department of Population, Family and Reproductive Health at the Bloomberg School of Public Health. David Serwadda, MMed, MSc, MPH, Nelson Sewankambo, MBChB, MMed, MSc, Stephen Watya, MBChB, MMed, and Godfrey Kigozi, MBChB, MPH, also collaborated on the study. The trial involved 4,996 HIV-negative heterosexual men. Volunteers were assigned at random to either intervention (circumcision performed by trained medical professionals in a clinic setting) or no intervention (no circumcision). All participants were extensively counseled in HIV prevention and risk reduction techniques. The trial reached its enrollment target in September 2005 and was originally designed to continue through mid-2007.

A 2005 trial conducted by a team of French and South African researchers in South Africa reported that circumcision reduced the risk of acquiring HIV by 60 percent.

For more information on the Kenyan and Ugandan trials of adult male circumcision, see the NIAID Questions and Answers document.

NIAID News Release

Public Affairs media contacts for the Johns Hopkins Bloomberg School of Public Health: Tim Parsons or Kenna Lowe at 410-955-6878 or