It wasn't supposed to be this hard. When HIV, the virus responsible for AIDS, was first identified in 1984, Margaret M. Heckler, then secretary of the U.S. Department of Health and Human Services, predicted that a vaccine to protect against the scourge would be available within two years. Would that it had been so straightforward.
Roughly 20 years into the pandemic, 40 million people on the planet are infected with HIV, and three million died from it last year (20,000 in North America). Although several potential AIDS vaccines are in clinical tests, so far none has lived up to its early promise. Time and again researchers have obtained tantalizing preliminary results only to run up against a brick wall later. As recently as two years ago, AIDS researchers were saying privately that they doubted whether even a partially protective vaccine would be available in their lifetime.
This article was originally published with the title Hope in a Vial.