Circumcision halves the risk of contracting HIV

Circumcision halves the risk of contracting human immunodeficiency virus (HIV), confirms US-Kenyan study published in the edition of the "Journal of Infectious Diseases."

In this study, Jared Baeten and American and Kenyan colleagues followed, between 1993 and 1997, 745 men employed by a trucking company in Mombasa, in which they controlled HIV status and circumcision.

Throughout the investigation, the men were asked about their sexual activity with three different partners (wives, casual partners, prostitutes) and were tested for HIV and other sexually transmitted infections. Then, at the end of study, the researchers calculated the probability of HIV infection in all three groups.

The likelihood of contracting HIV from a single act of intercourse has been estimated at 1 in 160 for all men.

This result is quite unexpected since the only studies on the subject showed a risk of transmission of HIV from one to 1,000 or less, a far from that calculated by the team of Jared Baeten rates. This explains this difference by the fact that, in the study that publishes several types of sex were taken into account, while others were conducted with discordant monogamous couples.

In addition, the authors observed a significant difference between circumcised and uncircumcised men, the latter having a higher risk than twice as likely to be infected, compared to the first (1/80 against 1/200).

This result confirms that obtained in previous studies, but it is only to take account of cultural characteristics that may influence the differences in sexual behavior, differences that may play a role in the risk of infection, the authors note. However, it appears that cultural differences in sexuality have no effect, and only being circumcised or not has an impact on the risk of being infected.

Considering that the rate of HIV transmission from a woman to a man can be more than twice as high if men are circumcised, and it is also significantly higher for multiple relationships are not followed, This may help explain why the virus spreads so rapidly in some parts of Africa and to define new strategies for prevention of infection, the authors conclude.