Because these denialist assertions are made in books and on the Internet rather than in the scientific literature, many scientists are either unaware of the existence of organized denial groups, or believe they can safely ignore them as the discredited fringe. And indeed, most of the HIV deniers’ arguments were answered long ago by scientists. However, many members of the general public do not have the scientific background to critique the assertions put forth by these groups, and not only accept them but continue to propagate them. A recent editorial in Nature Medicine  stresses the need to counteract AIDS misinformation spread by the deniers.
A very, very good and important article! Especially if you are struggling with various kinds of denialists on blogs all the time.
And you can also see other cool papers published today in PLoS Medicine.