This week, listening to the Guardian Science podcast, I had a treat. Caspar Melville, editor of New Humanist magazine, leader of something called the Rationalist Association, had been to see two films at the Cambridge Film Festival. One was a dreary creationist movie that famously misrepresented the biologists interviewed for it. This was obvious bad science, he explained. But the other was different: House of Numbers, a new film about Aids, really had something in it. I have now seen this film. It presents itself as a naïve journey by one young film-maker to discover the science behind HIV. In reality it’s a pernicious piece of Aids denialist propaganda.
All the usual ideas are there. Aids isn’t caused by the HIV virus: it’s caused by antiretroviral drugs themselves. Or poverty. Or drug use. Diagnostic tools don’t work, and Aids is just a spurious basket diagnosis invented to sell antiretroviral medication for a wide range of unrelated problems. The drugs don’t work. You’re better off without them.
It would take a book to address all this, and that blizzard of claims, perhaps, is the point of the film, with all the rhetorical devices that have been honed by Aids denialists and creationists over decades. It repeatedly overstates marginal internal disagreements about the details of HIV research, for example, to the extent that eighteen doctors and scientists who were interviewed in it have issued a statement saying that the director was ‘deceptive’ in his interactions with them, that it perpetuates pseudoscience and myths, and that they were selectively quoted to make it seem as if they are in disagreement and disarray, when in fact they agree on all the important facts.
At one point there is an extended sequence explaining that you can’t take a picture of the HIV virus; or maybe you can, but if you can, different scientists disagree on how, and on whether their method is best. This is an infantile world view, where stuff only exists if you can easily photograph it; where the internet, compound interest and magnetism don’t exist either.
There is a memorable skit on diagnostic tests, where the film-maker manages to find one woman working in a marquee in a shopping centre in Africa giving HIV tests, who accidentally misinforms him about why she is asking for information on his health-risk behaviours. In the film, this one slip by a junior member of staff in a shopping centre becomes a dramatic exposé: the HIV diagnosis is a tautology, it argues, a basket diagnosis for sick people of any kind who engage in risk behaviours; the blood test is unreliable, a piece of theatre; and the diagnosis is only made because the tester has asked if you are gay or inject drugs.
But people working on the front line of HIV testing are often told to ask about risk behaviours during a test, because testing is a great opportunity to educate people on prevention. What’s more – if you’re interested in the statistics of testing – knowledge about your pre-test likelihood of having a condition also helps the tester to correctly interpret any diagnostic test: because, as we have covered in this column, for terrorist screening, for predicting violence in psychiatric patients, indeed for anything, the likelihood of a false positive with any test is higher where the population prevalence of a condition is low. In any case, HIV tests are so reliable that in 2007 an HIV-negative woman won $2.5 million in damages after she was treated for Aids without a proper diagnosis, since there was no excuse for the mistake that her doctor made.
The show goes on. We see Neville Hodgkinson, the Sunday Times health correspondent who drove that paper’s denialist reporting in the 1990s. There is Peter Duesberg, who you will remember from when academic publishers Elsevier forcibly withdrew an article by him in one of their journals.
Then there is an interview with Christine Maggiore, who talks about her difficult decision to go against medical advice by refusing Aids medication, and how much better she feels as a result. What the film doesn’t tell you, oddly, is that Christine Maggiore’s daughter Eliza Jane died of Aids and PCP pneumonia three years ago, at the age of three; and, as I reported nine months ago, Christine Maggiore herself died two days after Christmas 2008 of pneumonia, aged fifty-two: this is finally acknowledged in the last two seconds of the film, at the end of the lengthy credits, in tiny letters.
Do you give idiots a wider audience when you respond to them? Are they marginal and irrelevant? I’d like to believe that they are. But the duping of Caspar Melville (who has since recanted), and the attention-seeking smugness of the Cambridge Film Festival, both suggest otherwise. I’ll never know the right way to deal with any of these people, and I’ll always welcome advice.