Jonny Steinberg writes in New Scientist [1]:
Despite the overwhelming evidence that HIV causes AIDS, a hardcore group still denies it (see AIDS denial: A lethal delusion). We explore five of the most common myths about AIDS.
MYTH: AIDS is not caused by HIV
DEBUNKING: This is the biggie, of course. As long ago as 1983, researchers first isolated HIV from people with AIDS. By 1985, they had developed a test showing that the overwhelming majority of people with AIDS have antibodies to HIV in their blood. They also showed that people who test HIV-positive and initially appear healthy go on to develop AIDS the vast majority of the time unless they are treated.
Links:
[1] http://www.newscientist.com/article/dn17326-five-myths-about-hiv-and-aids.html