A California woman may be the first person to be cured of HIV without a bone marrow transplant—in fact, she may have beat the virus without any treatment at all. In a recent report in Nature, researchers shed light on how Loreen Willenberg and about 60 other so-called elite controllers keep HIV in check. In these individuals, HIV’s genetic blueprint is locked away in the genome of resting immune cells in such a way that it can’t be used to produce new virus. Willenberg, who acquired HIV in 1992, has maintained control of the virus for decades without antiretroviral treatment. The researchers were unable to find any intact virus in more than 1.5 billion of her cells. “I believe Loreen might indeed meet anyone’s definition of a cure,” says study coauthor Steven Deeks, MD, of the University of California at San Francisco. The question now is whether scientists can develop treatments to enable the millions of typical people with progressive HIV to become more like elite controllers.