HIV Study Raises Caution About Circumcision
Wednesday, March 7, 2007
Men with HIV who get circumcised hoping they will be less likely to transmit the AIDS virus may have a greater-than-normal risk of infecting their partners if they resume sexual activity too soon after the operation.
That observation -- drawn from preliminary analysis of a study in Uganda -- threatens to complicate efforts to tout circumcision as a new weapon against HIV in Africa.
Specifically, it suggests that public health campaigns promoting circumcision must also include messages, directed principally at women, warning of the extreme hazard of intercourse with HIV-positive men who have just had the procedure.
The new data were presented yesterday to 75 government health ministers, scientists and policymakers from the World Health Organization and the U.N. AIDS program, and other experts meeting in Montreux, Switzerland, to develop guidance on using circumcision as a prevention measure.
Three studies, including two published last month, show that circumcision lowers a man's risk of acquiring HIV infection by half -- protection roughly equivalent to a moderately effective vaccine.
Researchers hope it might indirectly protect women as well. That could happen because circumcised men are less likely to have genital ulcers, which increase an infected person's risk of transmitting the virus. More broadly, if circumcision reduces HIV prevalence in a whole population, both sexes will benefit.
"The data that we have heard do not derail [the potential usefulness of circumcision] by any means," said Kevin De Cock, director of the HIV/AIDS department at WHO. "What it does do is provide a little more insight about the complexities that face us."
The research covers the Rakai district of southern Uganda, which has been hard hit by the AIDS epidemic. The study is being run by Ugandan researchers and scientists at the Johns Hopkins Bloomberg School of Public Health.
It involved about 1,000 HIV-infected men, half of whom were randomly assigned to undergo circumcision. The researchers looked at the experience of 124 couples in which the regular female partner was uninfected at the time the man had the procedure.
Among 70 men who were circumcised, 11 transmitted HIV to their partners. Of the 54 who were not circumcised, four passed on the infection. Almost all new transmissions occurred in the first six months. Because there were so few cases in either group, the findings were not statistically significant and may have occurred only by chance.
Of 12 men who resumed sexual activity before a physician had "certified" them as healed, three transmitted the virus to a partner. Of 55 men who waited, six transmitted the virus. Healing takes about one month.
An independent panel of scientists overseeing the study recommended that no new volunteers be enrolled because, even though the early findings were not statistically significant, it concluded that the original hypothesis -- that uninfected women would indirectly benefit over the short term from male circumcision -- was unlikely to prove true.
Much remains unknown. For example, some infected women may have acquired HIV from someone other than their regular partner -- a possibility the researchers will now look into by doing genetic fingerprinting on both the men's and the women's viruses.
One leader of the study, Maria Wawer of Johns Hopkins, said that for the moment "the need for extreme precaution and abstinence from sex in the post-procedure period cannot be overemphasized."
David Serwadda, a public health physician at Uganda's Makerere University, said the demand for circumcision, in male infants and in adults, has risen noticeably in his country in recent months.
Ezekiel J. Emanuel, a bioethicist at the National Institutes of Health who has written about ethical issues of circumcision research, noted that "this is not the first public health measure that will require careful education of the population that is being targeted."