There are few pleasures greater than that of attacking a prevailing orthodoxy, especially when it is upheld by people whose intellectual obtuseness is equalled only by their unscrupulousness. This is precisely what Joan Shenton, a producer of television documentaries about health thinks she is doing in Positively False.
She argues that the Human Immunodeficiency Virus (HIV) does not cause AIDS and may not even exist; that AIDS is not an infectious disease at all and is caused by such immuno-suppressive habits as intravenous drug abuse and anal sexual intercourse and that the reason the viral theory has been so widely accepted is an unhappy coincidence of the financial interests of certain scientists and those of international pharmaceutical companies.
For someone who claims to have frequently been the victim of unpleasant ad hominem strictures, she is quick to resort to the method herself, and sniffs out conspiracy quicker than a trained dog sniffs out cocaine. This is not to say that she makes no good points: for example, that there have been cases of illness exactly like AIDS which were HIV negative; that the experts grossly exaggerated the likely number of deaths from AIDS, that there are now people who have been HIV positive for more than 10 years who have shown no deterioration in their health; and that no virus of the HIV family had ever been shown before the advent of AIDS to cause any human illness.
Certainly, it was a startling coincidence that AIDS should have emerged so shortly after retro-virusses of the HIV family had been discovered. But
Ms Shenton gives these points rather more significance than they will... (unable to read)
She is a close follower - perhaps disciple would be a better word - of Peter Duesberg, the German-born molecular biologist now at the University of California who has long been the most insistent critic of the viral theory of AIDS. Unlike most scientists with more orthodox views, Ms Shenton gives him a glowing reference.
She is so in thrall to Duesberg that she fails to notice the wildness of some of his arguments. She quotes him as saying, for example, that HIV cannot cause AIDS because micro-organisms, whether bacteria or viruses, must produce their pathological effects soon after their entry into the body, or not at all. Has she not heard of tuberculosis, which may manifest itself 50 years after infection, or does she think that the great German bacteriologist Robert Koch too, was in the pay of the pharmaceutical companies?
Duesberg argues - and so therefore does Ms Shenton - that the presence of HIV in cases of AIDS does not imply causation. Indeed, they both regard HIV infection as a consequence of AIDS rather than its cause. A statistical association, they say, is not, after all, proof of causation. Quite right: but then Duesberg - and hence Ms Shenton - goes on to argue that AIDS is caused by (among other things) the use by homosexuals of drugs such as amyl nitrite, because there was a close statistical association between the first cases of AIDS and the use of amyl nitrite. Neither Duesberg nor Shenton see the contradiction.
In fact, all doctors who deal with AIDS see cases in which the sufferer has neither taken large quantities of drugs nor behaved promiscuously. The most parsimonious explanation is that AIDS is indeed an infectious disease, whose epidemiology much resembles that of Hepatitis B.
If there is one thing which this book illustrates clearly, it is the difficulty which most people have experienced in thinking about AIDS in a dispassionate way. They have regarded those who have the disease either as innocent martyrs to a cause, or as recipients of their just deserts for their disgusting behaviour. This intrusion of moral considerations into the question has frequently added to the contentiousness of the science.