VIRUSMYTH HOMEPAGE
THE HIV TESTS
AIDS; Words from the Front
By Celia Farber
Spin Nov. 1993
With the first HIV test in 1985, doctors thought they had discovered
an absolute oracle: Will the patient live or die? Celia Farber reports
on a recent, controversial paper that says the so-called AIDS test is too
flawed to be reliable.
Whether or not people ought to submit to
taking an 'AIDS test' has long been the subject of furious debate. The
impact of the life or lives of the people who do take the test if
it comes back positive is incalculable, since HIV is still largely
associated with surefire death.
The debate about the HIV antibody test
had been long, complex and anguished. No single diagnostic test
in the history of modern medicine has had such a momentous impact on the
lives of the individuals who rely on it. Since the beginning of the AIDS
crisis, people have had very dramatic responses to the test lapsing
into severe chronic depression and anxiety, quitting, or losing their jobs,
taking very toxic medications such as AZT and ddI, getting divorced, having
abortions, taking their lives and sometimes even other people's lives,
all based, not on diagnosis of AIDS, but merely a positive antibody
test.
Given that the test holds such power, its
flaws and shortcomings are extremely significant. Unfortunately, it is
only now that this immensely important subject is being investigated.
An Australian research team has published
a review article in the June 11 issue of Bio/Technology (E. PapadopoulosEleopulos,
V. Turner & J. Papadimitriou, 1993, 'Is a Positive Western Blot
Proof of HIV Infection?', Vol. 11, pp 696707) that calls into question
the accuracy of even the most accurate of the HIV antibody tests, the socalled
Western Blot test, which is said to be over 98% accurate. They state that
the test is seriously flawed on several counts: that it is not standardized,
that it cross reacts with nonHIV proteins, and that ultimately, it
is not reliable proof of actual infection with HIV.
Through their sharp critique of the methods
of testing for HIV, the authors raise astonishing points about the virus
itself what is known and not known, what is seen vs. what is assumed.
In the end, we get a dazzling insight into the precarious and fickle world
of retrovirology. How infinitely complex it is, compared to the simple
terms in which we've come to think of it.
The article, entitled 'Is a Positive Western
Blot Proof of HIV Infection?' was published in the June 11 issue of Bio/Technology
a science journal put out by Nature Publishing. The Australian
researchers, Eleni PapadopoulousEleopulos, Valendar F. Turner and
John M. Papadimitriou, conclude that '. . . the use of antibody tests as
a diagnostic and epidemiological tool for HIV needs to be reappraised'.
'A positive HIV status has such profound implications', they write, 'that
no one should be required to bear this burden without solid guarantees
of the verity of the test and its interpretation'.
Eleopulos and colleagues examine both HIV
antibody tests: the enzymelinked immunosorbent assay (ELISA) test,
the first test used to screen blood, which costs about $50, and the Western
Blot (WB) which is used to confirm a positive result on the ELISA, and
costs closer to $100. They sum up the problems with both tests by making
four major points: The tests are 1) not standardized, meaning that different
labs have different criteria for specifying what is negative and what is
positive; 2) not reproducible, meaning the test fails when tested against
itself, and repeated tests can be alternately positive and negative; 3)
proteins that are thought to be exclusive to HIV may instead be cellular
contaminants, or debris; and 4) there is no 'gold standard', for the HIV
test. Every diagnostic test must have a 'gold standard', and in this case
it would be HIV itself, but the authors argue, this is impossible since
HIV has never been isolated in pure form without cellular contamination.
Even the Polymerase Chain Reaction (PCR) the one test that looks
for HIV genetic material as opposed to viral antibodiesdetects only one
viral gene, the researchers argue, not the virus in its entirety. The PCR
is far more sensitive than the WB. It costs several hundred dollars and
is not commonly used.
The first test developed for HIV in 1985,
the ELISA test, was developed to screen out HIV from the blood supply.
It is highly sensitive, and very nonspecific, which means it gives a positive
result easily even when there is no HIV present. As many as four out of
five ELISA tests cannot be confirmed by Western Blot.
The ELISA is still the only test that is
used in the Third World, most notably Africa, where very alarmist projections
about HIV in the population have been made. In the United States, no person
is supposed to receive a result that is based only on ELISA, a test which
is used primarily as a first filter for the blood supply. Instead, a positive
test is given when a person has one or two positive ELISA tests, which
are them confirmed by a single WB test. However, the Bio/Technology
article details many cases of the test being inaccurate despite all
these steps being taken. Often, a second WB contradicts the first one.
For example, they cite data from a mass testing done by the U.S. Military
which contained some startling findings. There were 4000 people who had
two positive ELISAs followed by a negative WB (note: all of those 4000
would be called HIV positive in Africa and HIV negative in the West). But
perhaps more startlingly, there were 80 cases of people who had two positive
ELISAs and a positive Western Blot, followed by a negative followup
Western Blot. In other words, those 80 people, had they not been a part
of this particular, scrupulous study, would have been told they were HIV
positive, since a single positive WB is all that is required, but in fact
they were negative. How many other people who have been told, based on
a single positive WB that they are positive, are really negative?
Though it is not necessary to perform a
test in order to diagnose AIDS, a positive test does confirm, according
to Centers for Disease Control (CDC) regulations, an AIDS diagnosis. In
the absence of a positive HIV test, conditions get treated for what they
are; with a positive result, they all get labeled AIDS. The definition
of AIDS includes some 2530 different symptoms that occur in the presence
of a positive HIV antibody test. What few people are aware of, however,
is that the test is not an absolute, and there is a broad gray area that
many people may fall into. For instance, many people fall into a never
mentioned category technically called WBI, or Western Blot Indeterminate,
which means they hover between a positive and a negative result, and whether
they are told they are positive or negative may depend on which lab tests
their blood.
In both tests, ELISA and Western Blot,
a patient's blood is added to an antigen preparation and supposedly, if
HIV antibodies are present, they will react with the HIV proteins. But
the Bio/Technology paper raises some disturbing points about the
difficulty of developing a truly accurate diagnostic test, particularly
when the microbe in question, HIV, is barely present in the blood.
HIV has been notoriously difficult to isolate,
which is defined by Eleopulos as 'separating the virus from everything
else'. Consequently, The Western Blot detects patterns of proteins thought
to be specific to HIV. These are specified as 'p' for protein, followed
by a number which represents a molecular weight. HIV is recognized by proteins
p24, p17, gp41, gpl20, etc. These proteins have been said to be exclusive
to HIV, but Eleopulos and colleagues demonstrate that they are not. One
protein in particular, p24, is 'currently believed to be synonymous with
HIV isolation and viremia'. But Eleopulos and colleagues detected p24 antibodies
in a number of people who do not have HIV, including 13% of healthy patients
with generalized warts, one out of every 150 healthy people with no afflictions,
and 41 % of patients with multiple sclerosis, among others. Conversely,
p24 is notfound in all HIV or even AIDS patients, they point out.
A major problem with the Western Blot that
has never been assessed before is the fact that it cross reacts with other
microbes. People who have certain auto immune disorders, lupus and
rheumatoid arthritis for instance, have been known to test positive for
HIV even though they are not infected. The Bio/Technology paper
demonstrates how the test can cross react with other microbes, including
ones as common as malaria and TB.
Eleopulos, Turner and Papadimitriou report
on a paper that examined a tribe of Amazonian Indians who have no contact
with anybody outside their tribe and who have no incidence of AIDS, yet,
3.313.3% were HIV positive by Western Blot. 'The above data', the
authors speculated, 'means either that HIV is not causing AIDS' . . .'or
'. . . the HIV antibody tests are nonspecific'.
The study also details the fact that people
with severely depressed immune systems, hemophiliacs and blood transfusion
recipients for example, may test positive because they have so many foreign
proteins and antigens in their blood. Receiving foreign cells or proteins
from another person has been shown to cause immume disruption regardless
of whether or not HIV IS present.
The Bio/Technology paper specifies
the vastly different criteria used by different institutions to interpret
the WB test, and point out that an antibody test can only be meaningful
when it is standardized, that is, 'when a given test result had the same
meaning in all patients, in al1 laboratories, in all countries'. They sent
one blood sample to 19 different laboratories, which all showed it to be
HIV positive, but with wildly different band patterns. (With WB, individual
proteins are recognized visually as colored bands). In another instance,
a blood sample was sent 89 times to three laboratories; one pattern was
reported 64 times, another pattern 19 times, yet another pattern 4 times,
and once the sample tested negative.
The Food and Drug Administration (FDA)
has the most stringent criteria for the WB interpretation, followed by
the American Red Cross, and the Consortium for Retrovirus Serology Standardization
(CRSS). According to the Bio/Technology paper, less than 50% of
all AIDS patients have a positive WB when the FDA criteria are used. If
the criteria of the CRSS are used, the percentage of positives goes up
to 79%.
I asked a few scientists to comment on
the Eleopulos paper, all of them signatories in the Group For The Scientific
Reappraisal of the HIV Hypothesis. Dr. Charlie Thomas, a former Harvard
biologist, and founder of the Group for the Scientific Reappraisal of the
HIV Hypothesis, said he thought the Eleopolus paper was 'absolutely stupendous'.
'I think the HIV test has now been substantially challenged, and should
be withdrawn from the market until these questions are resolved', he said.
Dr. Robert RootBernstein, a critic
of AIDS scientific literature and author of Rethinking AIDS (FreePress)
was more reserved. 'I agree to a point just because you have a positive
WB doesn't mean you have HIV. But that doesn't mean you can throw out the
whole thing either. What I'm seeing when I read the literature is that
almost everybody who has antibody by WB has a positive PCR or co culture
if they go on to take those tests. And those are the papers that are ignored
in here. This is a point on which I disagree with Peter Duesberg [who says
that antibodies mean the infection is defeated]. I'm more than willing
to admit that there are people who don't have virus but they have the antibody,
and theoretically that could be a lot of people, but if you look at the
studies that have been done, it appears that almost everybody who has the
antibody actually is infected and does have a low level infection. I think
that a positive HIV test is still a strong predictor for getting AIDS'.
RootBernstein, in his book, has put
forth that AIDS is a multifactorial syndrome, or possibly an autoimmune
disease. 'To be real convincing', he continues, 'Eleopulos and colleagues
would have to come up with a more accurate marker for AIDS. I'm still an
agnostic about whether or not HIV is the cause, but it certainly is a good
marker for it'.
Dr. Peter Duesberg counters, 'If a virus
is to be claimed for a disease you want to see the virus, not an antibody
against the virus. An antibody is not a virus and it's not a predictor
for disease, it is only an indication that the virus has been neutralized,
in some cases a long time ago. If you try to diagnose polio, hepatitis,
measles you can find the virus, you don't have to mess around with antibodies.
Only in AIDS do we focus on the antibody'. Professor Alfred Hassig, who
was head of the Swiss Red Cross Blood Transfusion Service for thirty seven
years, commented. 'I think she [Eleopulos] is perfectly right. Every test
in serology, immunology has false positives and false negatives. But Western
Blot had been taken as a holy measure, and that is very unfortunate for
the person getting the result'. RootBernstein feels differently. 'By
the time you've got symptoms, does it really matter whether you've got
HIV or not? You still have to be treated for AIDS. The big issue there
is what we think is causing AIDS. I tell people to go see Dr. Joe Sonnabend
[a New York AIDS physician]; he won't treat the HIV, he'll treat everything
else. I think that's perfectly reasonable.
The other thing is, I've got a file that
keeps growing that there are people who are positive by ELISA, Western
Blot and PCR, who have low T cell counts, and they lose all those
things. They seroconvert to HIVnegative by all tests, and their
T cells stabilize or go up. They're usually people who alter their lifestyle.
It's important to point out is that even if you are positive that dosen't
mean you will get AIDS. At least in a small percentage of cases, people
can spontaneously eliminate an HIV infection'. The suggestion that people
'change their lifestyles', is one of the most inflammatory, frowned upon
ideas in the AIDS debate. I asked RootBernstein to be specific.
'All the cases I've read are in one of
two groups. Either limited exposure, like a girlfriend of a hemophiliac
who leaves him or they start practicing safe sex, or they're gay men or
IV drug users who quit. Quit the drugs or for gay men find a stable sexual
partner and practice safe sex. As I said in my book, I don't think there's
anybody who gets AIDS from a single exposure to HIV. Even if you look at
the transfusion cases, most of those people got 20 units of blood. Most
people are constantly reinfected'.
'I think she [Eleopulos] makes some very
excellent, important points', says Dr. Peter Duesberg of UC Berkeley, famous
for his views that HIV doesn't cause AIDS. 'She is correct to say that
it is not chemically pure, that it is contaminated with human cellular
proteins, and who knows what effect that has on the test result'.
Duesberg, unlike RootBernstein,
can see no value in the HIV antibody test, accurate or not. 'With all other
viruses the antibody tests, if they are done at all, are only there to
show that you are immunized, you don't need another shot', says Duesberg.
When asked what the response in the scientific
community to the Bio/Technology paper has been, Harvey Bialy, the
editor of the study and scientific editor of Bio/Technology, said,
'essentially none. I expected letters denouncing it, but I haven't received
a single one'. 'None of the testing companies have withdrawn their advertising',
Bialy said with a laugh.
'It sort of makes no difference what the
truth is because the antigen test for the p24 antigen has been thoroughly
discredited and is still used'. 'In this field [AIDS] what the facts are
is irrelevant', says Bialy. 'All people will say is that by pointing out
that the antibody test may not be accurate you're encouraging people not
to use condoms. No matter what you say which legitimately criticizes the
science of AIDS, the accusation is always that you're encouraging
people not to use condoms'. I called Australia to speak to the research
team, but they had been besieged by interview requests, though interestingly,
not a single one from the American media.
The debate about this paper will probably
be protracted. Some will denounce it as nonsense, others will follow its
leads. But it certainly ought to have a sobering effect on HIV testing
and the hysteria that goes with it. 'Why does this paper matter?' RootBernstein
asks rhetorically, 'It matters to all the people who test positive for
HIV by Western Blot and assume they have AIDS and are going to die, or
that they have to take AZT. She [Eleopulos] has convinced me that the tests
are not as good as most people think they are'. *
VIRUSMYTH HOMEPAGE