AIDS: TRUE OR FALSE?
By Neville Hodgkinson, Zambia
The Sunday Times (London) 5 Sept. 1993
faced with an enormous gap between reports of people testing HIV
positive and the number of people falling ill with AIDS, are calling
for a reappraisal of the idea that a positive test means a person
is liable to develop the disease.
They say that
different HIV test procedures in Africa produce such widely differing
results that their use should be re-examined. Yet at present some
people are being "frightened to death" by a positive diagnosis.
By the end of last year, the National AIDS Prevention and Control
Programme had received a cumulative total of 7,124 reports of full-blown
AIDS since the first cases were recorded in 1985. That represents
fewer than a thousand a year, relatively few in a nation of 8m people.
to screening surveys conducted late last year, as many as four out
of 10 sexually active people are now testing HIV positive, and a
million Zambians could be infected with the virus. Those findings
have horrified most politicians and AIDS workers, and spurred the
government into launching a new anti-AIDS campaign.
an MP and former cabinet minister, says the disease threatens to
orphan 2m children, and to take the lives of large numbers of staff
in companies, public utilities and government. "It is ripping
through the system. It is an absolute disaster," he said.
But Dr Francis
Kasolo, head of virology at the University Teaching Hospital in
Lusaka, said work in his department suggests the HIV figures cannot
be taken at face value.
found a big problem with false positives. When we repeat the tests,
there are a lot of disparities in the results. A test kit from one
manufacturer behaves differently from another's." The conclusion,
he said, was that "most of our results are more or less compromised".
Most of the
country's 80 testing centres were unable to afford a more expensive,
confirmatory procedure after an initial positive test. Even that
second test, known as Western Blot, produced widely differing results.
A third, rapid
test, still in use at some clinics, had been shown to produce up
to 40% false positive results in patients infected with malaria.
Blood "stickyness" of patients, unrelated to HIV, also
produced false positives.
Boayue, the World Health Organisation's representative in Zambia,
says the recent surveys show such a big increase in positive results
compared with six to seven years ago, when the proportion was only
about 5 to 8%, that he shares concern that the country is in the
grip of an HIV epidemic.
believes changes in the type of test kit used may contribute to
the changing picture. He says international aid for the developing
countries is often tied to use of materials provided by the donor
of the kits are supplied by the donors. If one decides not to provide
funds any more, we move to another who will, and the kits come from
that country instead. So the kits vary a lot: reporting can be high
or low, depending on the kit.
had individuals tested in one laboratory, and told they are positive,
who move onto another, where they are negative."
the picture had been further confused by a phenomenon called "transient
antibody to HIV" reported at a recent international meeting.
A Uganda-based professor of virology had seen that some HIV positive
patients subsequently tested negative.
with a recent call by scientists in Australia for use of HIV test
kits to be reappraised, in the light of evidence that many conditions
apart from HIV infection such as TB, malaria, malnutrition and multiple
infections can cause a person to test positive.
important that we address the whole issue of HIV in Africa scientifically,"
Kasolo said. "There is something going on that we do not understand."
Dr Sitali Maswenyeho,
a paediatrician at the University Teaching Hospital and former fellow
in AIDS research at the University of Miami, said he had long argued
against the HIV test. "It's non specific," he said. "The
test itself is killing a lot of people here. The stigma is doing
malnutrition, bad water, poor sanitation; and when on top of that
you are told you have an incurable disease, that really cuts off
on the tests' validity, the presence of a severe form of immune
system failure, affecting mainly sexually active people, is generally
There is argument,
however, over its causes. Kasolo questions the "new virus"
theory maintaining that a variety of sexually transmitted infections
might be responsible. This view is shared by many older Zambians.
22, an HIV positive man helping with the work of an AIDS education
and counselling organisation, says: "People in the villages
tell us it is not new, but that it has become worse because of promiscuity."
arguing that even in the past, people were promiscuous. But he supports
the challenge to HIV testing. *