Sorting It Out

New data from six U.S. cities show a dramatic rise in serosorting--the practice in which HIV-positive people choose to have sex only with others who also are infected. Prior to being diagnosed with HIV, the men surveyed reported having unprotected sex with HIV-negative partners or partners of unknown serostatus 75% of the time. But during acute infection--the approximate one-month period after acquiring HIV, during which viral levels in the blood are extremely high--they limited unprotected intercourse to only HIV-positive partners 97% of the time. 'This reflects a systematic shift...to behaviors that protect their sex partners,' says researcher Wayne Steward, an assistant professor of medicine at the University of California, San Francisco's Center for AIDS Prevention Studies.