The U.S. government has halted two clinical trials in which African men were circumcised to stop the spread of HIV after finding clear evidence that the procedure can prevent infection by the AIDS virus. The National Institute of Allergy and Infectious Diseases (NIAID) reported today that there is no need to continue the trials because both showed that circumcision reduces by 50% the chance of getting HIV from heterosexual intercourse.
The trials, in Kenya and Uganda, covered almost 8000 heterosexual, HIV-negative men. NIAID set up the studies after researchers noted that HIV rates are lower in areas where it is common to circumcise male babies. Both trials were scheduled to continue through mid-2007 but were stopped following a 12 December meeting by the group that monitors their data. In the Uganda trial of 2784 subjects--half of them uncircumcised controls--22 in the circumcised group and 43 in the control group had contracted HIV. In the 4996 men in the Kenya group, the numbers were 22 and 47, respectively. The findings mirror those from a South African study (ScienceNOW, 26 July 2005) that was halted early last year after French government researchers found a 60% reduction in HIV transmission risk with circumcision. All of the noncircumcised men used as controls in the NIAID trials will now be offered the procedure.
In a press statement, National Institutes of Health Director Elias Zerhouni noted that the findings "are of great interest to public health policymakers. ... Male circumcision performed safely in a medical environment complements other HIV prevention strategies." The World Health Organization announced that as a result of the African trials it will make specific policy recommendations for promoting male circumcision. But it warned that education efforts are necessary to keep men from "developing a false sense of security" and from taking risks that could negate the protective effect of circumcision.
A question that remains to be answered is whether circumcision of men already infected with HIV will prevent transmission to their female partners. A group at Johns Hopkins University in Baltimore, Maryland, is currently addressing that in a trial in Uganda.