Map of life expectancy at birth from Global Education Project.

Thursday, May 01, 2008

Denialism

Ana points out that you don't have to be African American to believe in myths about HIV. True enough, but I have been involved in public health work related to HIV for more than 15 years now, and I have never encountered the belief that HIV was created in a secret government laboratory among white people. What I have encountered, however, is the belief, indeed the passionate insistence, that HIV is not the cause of AIDS. This is in some respects essentially the opposite belief -- that the conspiracy has to do with so-called antiretroviral drugs, and suppression of the true causes of the disease, while HIV is actually harmless, or in some versions, does not even exist.

One of the most prominent perpetrators of this claim is Peter Duesberg, an organic chemist at UC Berkeley. Because he holds a tenured position at a prominent research university, HIV denialists have made him their champion. He has no stature within the relevant scientific community and is almost universally regarded as a crank motivated by envy and resentment. You don't have to take my word for it, these people have put together everything you need to know. However, to his supporters, he is the new Galileo, who was also despised for his radical theories. (In case you have any doubts, Avert lays out the proof that HIV is the cause of AIDS in detailed, systematic, and accessible fashion.)

Now, the interesting questions here are why these denialists movements arise, and how we can tell them apart from legitimate scientific dissent. After all, there was a time during which Stanley B. Prusiner was widely ridiculed for his claim that prions -- abnormally folded proteins -- could be agents of infectious disease, specifically Creutzfeldt-Jakob Disease. Prusiner ultimately won the Nobel Prize for his discovery. Could Duesberg be another Prusiner, and why am I so sure he isn't?

First of all, Prusiner was not entirely isolated. The prion hypothesis had been raised earlier. It was a challenge to accepted dogma, and so the initial resistance was not surprising. It is appropriate and healthy for scientists to question new hypotheses and throw up resistance to their acceptance. Claims that step outside of existing frameworks have a high burden of proof. Now, HIV was not entirely a radical idea -- retroviruses were known, as were viruses which cannot be eradicated by the immune system, and viruses which take a long time to produce disease. However, it is certainly novel in preferentially attacking cells of the immune system, and is generally unlike other known viruses that infect humans.

So there was nothing wrong with Duesberg initially raising objections. The problem is that every objection he has raised has been refuted, and yet he continues to insist on his premise, either coming up with new objections, new ever more stringent standards of proof, and ultimately simply ignoring the truth. This is the same way creationism works, and global warming denial. Rather than pursuing the evidence where it leads, the denialists start with the conclusion and reason backward from there. For a time it may be possible to identify gaps in the chain of evidence and reasoning that lead to evolution, or global climate change, or HIV, but ultimately these theories have withstood the test. The evidence is incontrovertible, but the denialists cannot see it.

The essence of the problem is that their stake is not in the truth, but in some other benefit they gain from their belief. The consolations of faith, the opportunity to make billions by burning fossil fuel, or in Duesberg's case the conviction that one is the intellecutal superior of all the other scientists. For his champions, there is the opportunity to con Harper's Magazine into buying your article, or otherwise make money off of snake oil. The cost, however, is people's lives.

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