A new genetic study of HIV isolated from blood samples taken in the late 1970s clarifies where and when the epidemic began in the United States—and it does not involve a man infamously labeled as “Patient Zero.” Using a technique known as the molecular clock that allows researchers to create a family tree of different genetic isolates and place them in time, Worobey explained in a presentation at an HIV/AIDS meeting in Boston last week that the virus likely came to New York City in 1970 and was linked to viral isolates then circulating in Haiti and other Caribbean countries. Dugas’s isolate fell in about the middle of the tree they created of early U.S. isolates, and clearly showed that he was not Patient Zero—the first person to introduce the virus—in the United States.
Photo credit: Stephen Fuller. Wellcome Images (CC BY-NC-ND 2.0)