The New England Journal of Medicine reports that male circumcision significantly reduced the incidence of HIV infection among men in three clinical trials.

In this new research 5534 HIV negative, uncircumcised male subjects between the ages of 15 and 49 years were enrolled in two trials of male circumcision for the prevention of HIV and other sexually transmitted infections.

Of these subjects, 3393 were HSV-2–seronegative at enrollment and 1684 were randomly assigned to undergo immediate circumcision (intervention group) and 1709 to undergo circumcision after 24 months (control group). After two years subjects were tested for HSV-2 and HIV infection and syphilis, HSV-2 was detected in 114 circumcised men compared with 153 uncircumcised men. HPV was detected in 42 circumcised men compared with 80 uncircumcised men.

The study authors concluded that in addition to decreasing the incidence of HIV infection, male circumcision significantly reduced the incidence of HSV-2 (herpes simplex virus) infection and the prevalence of HPV (human papillomavirus) infection. Herpes is associated with an increased risk of HIV infection.

The image is an electron micrograph of HIV budding from cultured lymphocyte.
References:
1. Aaron A.R. Tobian, et al. Male Circumcision for the Prevention of HSV-2 and HPV Infections and Syphilis. The New England Journal of Medicine, Volume 360:1298-1309.