AIDS: Science at a Crossroads

vaccine is highly unlikely to be responsible. First, HIV is unlikely to have survived in the kidney cells
used to grow the vaccine. Second, the vaccine was given by mouth and HIV rarely survives in the gut.
Thirdly, the geography and the epidemiology are wrong: if HIV's forerunner had been transmitted first
to humans in the Congo on this scale, researchers would have expected to see an epidemic there first.
As has been shown above, there is no evidence of such an epidemic during the 1960s.
In years to come, HIV will presumably continue to mutate. It is possible that either more virulent or
less virulent strains could emerge. What seems most certain is that the situation will become even more
diverse and complex than it is today.
Is AIDS a myth?
For the past eight years or so, a small but vocal minority in the AIDS research community - and a
group of supporting journalists - has argued that HIV is not the cause of AIDS. Led by Dr Peter
Duesberg, a virologist at the University of California, Berkeley, the dissidents argue that HIV is just a
harmless passenger virus that happens to be found in all the people who get AIDS.
The factors that cause the disease are not HIV at all, they argue, but lifestyle factors, such as use of
recreational drugs or having many sexual partners. They claim AIDS can even be caused by the
antiviral drugs used to combat HIV. such as AZT. Duesberg and others, such as Dr Robert RootBernstein, argue that the evidence linking HIV with AIDS is unconvincing. They believe that AIDS in
Africa scarcely exists or has been grossly exaggerated; and they believe that current testing methods
are not valid.
Duesberg is a respected virologist and a member of the National Academy of Sciences in the US. A
small number of scientists support him, but the overwhelming majority say he is selective with data and
ignores the published literature. Nevertheless, his views have been publicised and enthusiastically
promoted by some sections of the media, such as the Sunday Times in the UK.
The gaps in scientific knowledge about HIV are considerable. There is a need for challenges to the
established research community, but the questions that have yet to be answered are not those that
Duesberg is asking. Unfortunately, many scientists have preferred to ignore Duesberg rather than take
issue with him. This has two damaging effects: it allows him to gain status with the media for being a
stifled dissenter; and it diverts public and scientific attention from the real, more demanding
unanswered questions about HIV.
The main points made by the "AIDS dissidents" are the following:
* HIV has not been shown to meet the classical requirements, known as Koch's postulates, that must
be met if a microbe is to be identified as the direct cause of a disease. Robert Koch, a German
microbiologist, discovered the bacillus that causes TB, Mycobacterium tuberculosis, in 1882. His
work was central in establishing the theory that germs cause disease. To prove that a microbe
causes disease, Koch said, it must be isolated from a sick animal, given to a healthy one and seen
to cause the same symptoms; then it must be isolated again.
However, Koch's postulates are in practice difficult to meet with a number of infectious diseases
- including, ironically, tuberculosis. In the case of HIV, however, there may now be a near-perfect
case, resulting from a disastrous laboratory accident in the US in which three workers were
accidentally infected with purified, cloned HIV. In 1993, William Blattner of the National Cancer
Institute reported that the three all had falling CD4 counts and one had developed Pneumocystis
carinii pneumonia. None of the individuals had other risk factors for infection (7).
* Drugs, alcohol, a buildup of stresses on the immune system from contaminated blood products. and
too many sexual partners, can all be blamed for destroying the immune system and causing AIDS.

But lifestyle appears to be less important than Duesberg believes. Data from several sources
suggest that haemophiliac men and gay men infected with HIV tend to develop AIDS at roughly
the same rate (8). For the vast majority of people affected by HIV in the developing world, the
"lifestyle" factors that Duesberg blames are irrelevant. For most, recreational drugs are not

Panos Briefing: AIDS: SCIENCE AT A CROSSROADS 8