A recent study of men co-infected with herpes simplex virus type 2 (HSV-2) and HIV revealed that drugs used to suppress HSV decrease the levels of HIV in the blood and rectal secretions, which may make patients less likely to transmit the virus. This study is published in the November 15 issue of the Journal of Infectious Diseases, now available online. Most HIV-infected persons are also infected with HSV-2, which is the major cause of genital herpes. Prior studies demonstrated that the risk of passing HIV to a sexual partner is greater when the HIV-infected person has genital ulcers caused by HSV. Previous studies among HIV/HSV-2 co-infected persons and test-tube research have also demonstrated that HIV levels are increased during genital HSV reactivation.