March 14, 2008
Study Shows Male Circumcision Provides No Protection against HIV for Women; Another Says It Reduces Genital Infections in Men and Women
According to a new study, male circumcision, which reduces by about 60 percent the likelihood that a male will become HIV infected through sex with an HIV-infected female, provided no benefit to the HIV-uninfected female partners in the trial. The trial involved HIV-infected males who were circumcised as part of the trial and their HIV-uninfected wives. What’s more, the study, conducted in Rakai, Uganda, showed that in couples that resumed sex before the man's circumcision wounds fully healed, the women were at higher risk of HIV infection. The research, however, confirmed that HIV-infected men who are circumcised have a lower incidence of genital infections than their uncircumcised counterparts. Some genital infections may increase the likelihood of HIV transmission between partners.
Results of the study, which was conducted by researchers at John Hopkins University, Uganda’s Makerere University and the Rakai Health Science Program, were presented at the 15th annual Conference on Retroviruses and Opportunistic Infections (CROI) in Boston on February 4.
A second study, also conducted in Rakai by researchers at the same institutions, together with the U.S. National Institute of Allergy and Infectious Diseases, confirmed the finding that circumcised men have a lower risk of contracting genital infections that could exacerbate the spread of HIV, and found the benefit was conferred to their wives as well.
IAVI strongly supports the development of a range of new prevention tools to combat HIV/AIDS and recognizes the importance of circumcision as an effective HIV prevention tool for men and as a way to reduce genital infections in both men and women. It is important to remember, however, that circumcision will not completely protect circumcised men from HIV infection, nor does it protect women who have sex with circumcised men, as the first study shows. Circumcision is a surgical procedure that requires trained personnel, sterile instruments and close adherence to post-surgical instructions to maximize its benefits and to reduce the chance of unintended harm, as the study also shows. Proper implementation is urgently needed, but requires significant strengthening of healthcare infrastructures throughout Africa and elsewhere.
The finding that male circumcision does not protect women from HIV infection underscores the need for more and better HIV-prevention tools that women can initiate and control unilaterally. A vaccine would be the ultimate prevention option for women and girls, who comprise 48 percent of people living with HIV globally. IAVI continues to believe that a preventive AIDS vaccine is the best hope of ending the pandemic. Even a modestly effective vaccine could save millions of lives.
Two Major Herpes Suppression Trials Show Treating Genital Herpes Does Not Reduce Risk of HIV Infection
In other prevention news, disappointing findings from a study conducted by the University of Washington and the HIV Prevention Trials Network, also presented at CROI, confirmed twice daily treatment with the antiviral drug acyclovir does not reduce the risk of HIV infection in women and men who have sex with men who are infected with herpes simplex virus type 2 (HSV-2), the virus that causes genital herpes. The trial, dubbed study 039, took place at nine study sites in five countries—South Africa, Zambia, Zimbabwe, Peru and the United States. It was hoped that acyclovir would suppress HSV-2 outbreak activity and the ulceration that may make it easier for HIV to cross the mucosal membrane and enter the bloodstream.
Data from a second study, published on March 12 in the New England Journal of Medicine, also showed no evidence that the HSV suppressive therapy acyclovir, when taken twice daily, decreases the incidence of HIV infection. Researchers from the London School of Hygiene and Tropical Medicine enrolled 821 HIV-negative women aged 16 to 35 at recreational facilities in Tanzania between January 2004 and May 2006. Because previous biologic and epidemiologic studies demonstrated that HSV-2 infection increases the risk of acquiring HIV, researchers thought it might be plausible for HSV suppression therapy to reduce HIV acquisition. However, the results indicated that the women who were in the drug treatment group were not any less likely to become infected with HIV than the women in the placebo group.
The inability of herpes simplex therapy, according to these study results, to reduce the risk of HIV infection underscores the need for additional research into new prevention tools in the hope of developing novel options that are efficacious.