Medicine: The Appalling Saga of Patient Zero

Club Baths, San Francisco, November 1982 . . . When the moaning stopped, the young man rolled over on his back for a cigarette. Gaetan Dugas reached up for the lights, turning up the rheostat slowly so his partner's eyes would have time to adjust. He then made a point of eyeing the purple lesions on his chest. "Gay cancer," he said, almost as if he were talking to himself. "Maybe you'll get it too."

-- Randy Shilts, And the Band Played On

Since the early days of the AIDS epidemic, researchers have reasoned that a handful of people -- maybe...