In the early 1990s a few gay men whose partners had developed AIDS found that, in spite of numerous unprotected exposures, they remained HIV-negative. Realizing they were exceptional, they asked repeatedly to be studied. Finally, scientists at the Aaron Diamond AIDS Research Center in New York began to investigate the exposed uninfected, or “EU,” men.
Can a person be truly resistant to HIV? What could account for this? How common is this trait in the general population?