AVERT
Evidence that HIV causes AIDS

Introduction
"AIDS is caused by infection with a virus called human immunodeficiency virus (HIV). This virus is
passed from one person to another through blood-to-blood and sexual contact."1

That's the standard explanation of what causes AIDS. But what evidence do scientists have to support
this theory? And why do some websites say that the world has got it terribly wrong - that HIV does
not cause AIDS at all?

As an independent AIDS organisation founded in 1986, AVERT has taken a keen interest in the ongoing
debate about what causes AIDS. As well as investigating the consensus position, we have followed and
carefully considered the arguments of the dissident minority who claim that HIV is harmless or even
that it might not exist. This topic is vitally relevant to how our organisation works to prevent
people developing AIDS and to help those who are suffering.

It is AVERT's considered opinion that the evidence that HIV causes AIDS is abundant and conclusive.
This page outlines some of that evidence, while also mentioning how some dissidents have interpreted
things differently. In particular, we'll look for proofs of the following:

AIDS is a new epidemic disease
AIDS does not occur without HIV
HIV infection is the only factor that predicts who will develop AIDS
Surveillance statistics support the HIV theory
Modern antiretroviral treatment is highly beneficial.
(Este artículo también se encuentra disponible en español.)

Who doubts that HIV causes AIDS?
By far the most significant scientist to question the HIV/AIDS theory is Professor Peter Duesberg, a
virologist at the University of California at Berkeley, who first wrote about this topic in 1987.
Throughout the 1990s and into the new millennium, as HIV/AIDS researchers announced many new
discoveries and amassed huge volumes of data, Dr Duesberg remained unconvinced. He admits that HIV
exists, but he maintains that it is harmless, and that AIDS is caused by non-contagious factors
including drug abuse, malnutrition, and even the very drugs used to combat HIV.2

Other dissidents (often called "denialists" by their opponents) include the Perth Group of medical
scientists and physicians from Australia. The Perth Group (led by Eleni Papadopulos) claims that
nobody has conclusively proven the existence of HIV, so any proof that HIV causes AIDS has no
foundation.3

Dissident arguments have received attention from the popular media, as well as from scientific
journals. And with the rise of the Internet, alternative views have found a much wider audience, so
that scarcely anyone interested in AIDS can have failed to hear of them.

Some of their followers are intrigued by conspiracy theories involving sinister drug companies or
government persecution of minority groups. But alternative explanations can also appeal to those
diagnosed with HIV or AIDS, who read that their condition might not be fatal, that they shouldn't
take toxic drugs, and that unprotected sex poses no risks. Even a few AIDS service organisations have
adopted non-HIV viewpoints.4

However, the proportion of scientists who doubt that HIV causes AIDS is tiny, and shows no sign of
increasing. Interest in dissident views appears to have dwindled after the excitement surrounding
Thabo Mbeki's AIDS panel and the Durban Declaration in 2000. It seems likely that new and better
evidence, including the obvious benefits of modern drug treatments, has caused many former-dissidents
to change their minds.

What is AIDS?
Before we can begin to look for a cause, we must first work out exactly what type of illness we are
talking about.

In early 1981, doctors in New York and California began to report some bizarre new disease outbreaks.
In both places, previously healthy young men were showing up with rare illnesses including Kaposi's
sarcoma (a kind of tumour) and PCP (a type of pneumonia), which until then had been virtually unheard
of among such people. Within months, dozens of similar cases had been reported in 23 American states
and in the UK, representing the start of a massive and unprecedented epidemic.5

Doctors soon discovered a distinctive feature of these cases. More than anything else, the men were
lacking a specific type of white blood cell, which is essential to a healthy immune system. Normally,
people have between 600 and 1,500 "CD4+ cells" (also called T helper cells) in each cubic millimetre
of their blood. But the men with the strange new disease typically had very much lower levels. This
immune deficiency explained why they were so vulnerable to disease.

The cases were clearly related in time and by population group (initially gay men and injecting drug
users). No cause of immune deficiency could be found, but it was clearly not inherited. Scientists
therefore grouped together all of these strange new cases under the heading "Acquired Immune
Deficiency Syndrome" - or AIDS for short.

In 1982, no-one claimed to know the cause of AIDS, so the first definition was based on the diagnosis
of one of 13 rare diseases known to be linked to immune deficiency (including Kaposi's sarcoma and
PCP) "occurring in a person with no known cause for diminished resistance to that disease".6 Over the
years, the US definition has been refined as hundreds of thousands of similar cases have been
documented, sometimes involving other diseases, but always associated with the same distinctive
immune deficiency.7 Other definitions have also been developed to suit different situations elsewhere
in the world.8

The latest US AIDS definition was created in 1993. Under this definition, someone has AIDS if they
have one of 26 specific diseases (28 in children) but no known cause of immune deficiency other than
HIV (with some diseases, a positive HIV test is required); or if they have a CD4+ cell count below
200 cells per cubic millimetre of blood, or less than 14% of all lymphocytes, plus a positive HIV
test.9

Europe and Canada have similar AIDS definitions to the US, but do not include low CD4+ cell counts.

Problems with the definition?
The definition of AIDS usually requires a positive HIV test. This means that any connection between
HIV and AIDS is artificially strengthened because any cases of "HIV-free AIDS" are discounted. In
other words, the definition already assumes that HIV causes AIDS, so it can't be used to prove that
theory. However, it is possible to redefine AIDS without reference to HIV or even to any other
diseases.

The alternative definition of AIDS requires a CD4+ cell count consistently below 200 cells per cubic
millimetre of blood, which cannot be explained by any factor other than HIV (such as cancer,
malnutrition, radiation or chemotherapy). No HIV test is required.

It turns out that the vast majority of people diagnosed with AIDS fit these criteria. They form a
population that barely existed before 1980, but which now numbers hundreds of thousands in the USA
and Europe alone. People with such severe immune deficiency are at very high risk of developing
serious illnesses and usually die within months (unless they take antiretroviral drugs).10 11 12 We
can use this simple, unambiguous definition to test the association between HIV and AIDS.13 14

How can we prove that HIV causes AIDS?
Koch's Postulates
In the nineteenth century, the German scientist Robert Koch developed a set of four "postulates" to
guide people trying to prove that a germ causes a disease. Scientists agree that if HIV satisfies all
of these conditions with regard to AIDS then it must be the cause of AIDS:15

Koch 1: The germ must be found in every person with the disease
Koch 2: The germ must be isolated from someone who has the disease and grown in pure culture
Koch 3: The germ must cause the disease when introduced into a healthy person
Koch 4: The germ must be re-isolated from the infected person
Other evidence
Even Koch recognized that in some cases not all of his conditions could be met, so other evidence
should also be considered. This is particularly true when the germ is a virus rather than a
bacterium.16 Modern scientists are willing to consider a wide range of evidence. In particular, we
can ask five key questions:

Do surveillance statistics show a relationship between HIV and AIDS?
How well does HIV infection predict illness and death?
Do drugs designed to combat HIV benefit people with AIDS?
Are there any credible causes besides HIV?
What can we learn from Africa?
We'll address these questions after looking at Koch's Postulates.

Koch 1: The germ must be found in every person with the disease
The US Centers for Disease Control and Prevention (CDC) defines a condition called idiopathic CD4+
T-lymphocytopenia, or ICL for short. Someone is diagnosed with ICL if they have a CD4+ cell count
below 300 cells per cubic millimeter, or 20% of all T lymphocytes, on at least two occasions, but
have no detectable HIV infection, nor any other known cause of immune deficiency (such as cancer
therapy). As many dissidents have pointed out, this is essentially a definition of HIV-free AIDS. So
just how common is this condition?

In 1993, a CDC task force published the results of an exhaustive survey of ICL in the USA. They had
reviewed 230,179 AIDS-like cases reported since 1983 and identified 47 patients with ICL (plus 127
uncertain cases). All of the other people with AIDS who had received an HIV test produced a positive
result. What's more, the team closely investigated the ICL cases and discovered that they didn't fit
the usual AIDS profile. There were 29 male and 18 female patients, and 39 of them were white (4
others were of Asian descent). In 29 cases, the researchers couldn't fit the people into conventional
risk groups for AIDS (homosexual men, haemophiliacs, injecting drug users, and the sexual partners of
such groups). Whatever these 47 cases represent, they don't seem to be typical of the massive
epidemic that we're interested in.17

The findings of the ICL survey are backed up by large-scale monitoring studies, including the
Multicenter AIDS Cohort Study (MACS). During the MACS, scientists monitored the health of 2,713 gay
and bisexual men who tested negative for HIV antibodies. Over several years, only one of these men
had persistently low CD4+ cell counts, and he was undergoing cancer therapy designed to weaken his
immune system. Similar results have been found among blood donors, recipients of blood and blood
products, injecting drug users and other groups: severe immune deficiency is virtually non-existent
among those who test HIV-negative.18

As Dr Duesberg has pointed out, quite a lot of people (mostly in the early 1980s) have been diagnosed
with AIDS in the USA despite never taking an HIV test, and nobody knows whether these people were
HIV-positive or not. However, based on the much larger sample of people who have been tested, Koch's
first postulate has certainly been satisfied. The only way by which dissidents have been able to come
up with significant numbers of HIV-free "AIDS" cases is by using much looser definitions of AIDS.
Such definitions include many people with milder immune deficiency, which is generally not fatal.19
20

What about false positive test results?
Diagnosis of infection using antibody testing is one of the best-established concepts in medicine.
The World Health Organisation and the US National Institutes of Health agree that modern HIV tests
are extremely reliable, and are even more accurate than most other infectious disease tests.21 22

Nevertheless, some dissidents have tried to dismiss the association between AIDS and HIV by claiming
that many of those who test positive are not really infected with HIV. In particular, Christine
Johnson has listed dozens of conditions reported to have produced false positive reactions on at
least one occasion (under particular circumstances, using particular test kits).23

It is true that no test is perfect. However, what the dissidents usually don't mention is how rare
the reports of false positive results have been, especially in recent years. Nor do they mention that
every person who uses a test kit is trained to spot the telltale signs of a suspicious result, and to
keep testing by various methods until no doubt remains. The conditions that cause false positive
results are not only very uncommon, but are also typically short-lived, whereas HIV infection does
not go away.24 25

The dissident theory cannot satisfactorily explain why scientists have been able to use various
techniques to detect the virus itself in virtually everyone with AIDS, as well as in most people with
positive antibody test results, as explained in the next section. These methods (including DNA PCR,
RNA PCR and viral culture) are not affected by any of the factors said to produce false positive
results in antibody testing.

Nor can the alternative theory fully explain why the association between AIDS and antibody test
results is so exceptionally strong: virtually everyone with AIDS tests positive, while more than 99%
of the US public tests negative. And it cannot explain why the proportion of people testing HIV
positive should have increased so dramatically over time. For example, the proportion of South
African women testing HIV positive in annual antenatal surveys rose from 0.8% in 1990 to 10.4% in
1995, 24.5% in 2000 and 29.5% in 2004. The age distribution of these data is similar to that of other
sexually transmitted infections.26

Koch 2: The germ must be isolated from someone who has the disease and grown in pure culture
Koch required that the germ be isolated from all other material that could possibly cause disease, so
that his third and fourth postulates could be properly tested.

In May 1983, Luc Montagnier and his colleagues in France reported the isolation of a virus they named
LAV, which infected and killed CD4+ cells. A year later, the American Robert Gallo announced he had
isolated a virus called HTLV-III and found a way to grow it in culture. It was later discovered that
the two viruses were genetically indistinguishable, and they were renamed HIV.27

Researchers have been able to isolate and culture HIV from most AIDS patients whom they have examined
(as well as from many other people with HIV antibodies).28 They have isolated the virus from blood
cells, blood plasma, lymph nodes, semen, vaginal fluids, amniotic fluids, bone marrow, brain,
cerebrospinal fluid, intestines, breast milk, saliva, urine and tears, and cultured it in various
cell types.29 Images taken using electron microscopy and other techniques have shown virus-like
particles that have the size, shape, structure, density, proteins and behaviour expected of
retroviruses.30 31

Techniques developed in the mid-1990s have made it much easier to extract and sequence the complete
genetic material (genome) of an isolated virus.32 33 The Los Alamos database now contains hundreds of
full-length HIV genomes from around the world, each containing the same nine genes.34 Based on
genetic similarities and differences, these sequences have been used to define family trees of HIV
types, groups and subtypes as well as hybrids called recombinant forms.35

Whole or partial HIV genomes have been detected in numerous AIDS patients, using a technique called
PCR (the same technology is used to find DNA evidence with which to convict murderers or to settle
paternity suits, as well as to detect the germs that cause hepatitis, tuberculosis and other
diseases). Almost everyone who tests positive for HIV genetic material also tests positive for HIV
antibodies, and vice versa, while those who test negative for one thing also lack the other.36 People
who have been exposed to the same source of infection contain genetically very similar HIV strains -
similar enough for court convictions.37

Scientists have used a standard technique of genetic science called molecular cloning to obtain
highly purified HIV. Genetic material extracted using PCR or other techniques has been introduced
into bacteria or other cells (usually using phages or plasmids), which then produce many exact copies
(clones) of the viral genes. If cloned viral genomes are inserted (transfected) into human cells then
they produce a new generation of infectious HIV particles, which are free from contamination.38

Virtually all experts agree that HIV has been isolated according to the most rigorous standards of
modern virology, meaning that Koch's second postulate has without doubt been satisfied.

What about the Perth Group?
A small band of Australian scientists and physicians claims that HIV has never been properly
isolated. The Perth Group has never said that HIV doesn't exist; rather they say that HIV has never
been conclusively proven to exist. They don't trust any HIV tests, because they have not been
verified using their "gold standard" of isolated virus. The Group uses the isolation argument to
dismiss just about every type of evidence that HIV causes AIDS.39

Virtually all virologists believe that the Perth Group's conditions are unnecessary. They say nobody
has ever used such rules to isolate any type of virus, and that other techniques are much more
effective. According to the Perth Group's rules, nobody has isolated or proven the existence of the
viruses said to cause small pox, influenza, measles, mumps and yellow fever.

Experts argue that the Group's rules are unreasonably demanding and impossible to satisfy fully, even
though their main requirements have already been met.40 41 Dr Duesberg is among those who have tried
in vain to persuade the Perth Group that HIV definitely exists and has been isolated using the most
rigorous methods available.42 43 44

The Perth Group appears to have only two active members: a medical physicist called Eleni
Papadopulos-Eleopulos and an emergency physician called Valendar Turner. In late 2006,
Papadopulos-Eleopulos and Turner testified in the appeal trial of Andre Chad Parenzee, an
HIV-positive man convicted of endangering life by having sex with three women without informing them
of his infection. The two witnesses intended to demonstrate that HIV had not been proven to exist;
that HIV tests were unreliable; and that there was no evidence of HIV transmission through sex.

The presiding judge concluded that the Perth Group members had no qualifications or practical
experience in virology, immunology or epidemiology, and were not qualified to express opinions about
the existence of HIV, or whether it had been shown to cause AIDS. The judge found that the pair
relied entirely on the work of others, which they often took out of context and misrepresented. Their
arguments were found to lack plausibility and cogency, and to have "minimal" probative value. "I am
satisfied that no jury would conclude that there is any doubt that the virus HIV exists," said
Justice Sulan. "I consider no jury would be left in any doubt that HIV is the cause of AIDS or that
it is sexually transmissible."45

Koch 3 and 4: The germ must cause the disease when introduced into a healthy person, and the germ
must be re-isolated from the infected person
The third and fourth postulates are much harder to prove. It's considered unethical to deliberately
infect someone with pure HIV, so such an experiment has never taken place. However, there is no
reason why the transmission has to be deliberate.

There have been three reports of lab workers developing immune deficiency after accidentally exposing
themselves to purified, cloned HIV. As mentioned above, such cloned virus is free of all
contamination from the original source. None of these people fitted conventional risk groups for the
disease. In each case, HIV was isolated from the individual and, by genetic sequencing, was found to
be the strain to which they'd been exposed. One of these workers developed PCP and had a CD4+ cell
count below 50 cells before starting antiretroviral treatment.46

Still, three examples don't make a totally conclusive proof, so it's worth looking for more evidence.

One line of argument can be based on animal experiments.47 In some studies, chimpanzees deliberately
infected with HIV-1 have gone on to develop AIDS-like conditions (though this appears to be rare),48
while HIV-2 has had the same effect on baboons.49 Macaque monkeys have developed AIDS after being
infected with a hybrid virus called SHIV, which contains genes taken from HIV.50 And in mice
engineered to have a human immune system, HIV produces the same patterns of disease as in humans.51

If we're prepared to bend the rules a bit further, we can look at people who've been infected with
non-purified HIV. Such cases at least suggest that AIDS is infectious, though they don't rule out the
possibility that more than one germ is involved.

Scientists have documented numerous cases of people developing AIDS after becoming infected with HIV
as a result of blood transfusions, drug use, mother-to-child transmission, occupational exposure and
sexual transmission. In such cases, they have recorded the development of HIV antibodies
(seroconversion) using a series of blood tests, before progression to AIDS. Seroconversion is often
accompanied by a mild flu-like illness or swollen glands.52

Until the mid-1990s, nobody claimed that HIV had fulfilled Koch's last two postulates. Even today,
the proof is not quite perfect. But most scientists believe the evidence is now strong enough to put
the case beyond all reasonable doubt.53

Surveillance statistics
Most countries with high rates of HIV have conducted regular national HIV surveillance studies since
the early 1990s. AIDS case reporting began much earlier, in the early 1980s. All of the data are
available to the public online.

HIV and AIDS in Thailand, 1984-2000
AIDS case statistics are generally expected to underestimate the scale of AIDS epidemics, especially
in African countries, because many cases go unreported. However, it is reasonable to assume that
trends in the number of reports should roughly correspond to trends in the overall epidemic.

Of all countries, Thailand has one of the best records of HIV surveillance, with around 70 sites
included each year since 1990. Thailand also has relatively good infrastructure for the reporting of
AIDS cases. On the right is a graph showing trends in Thai statistics between 1984 and 2000.54

The graph shows that during the 1990s there was a dramatic increase in AIDS case reports. This
increase came after a sharp rise in HIV prevalence, with a time lag of a few years (nearly 200,000
HIV tests conducted between 1985 and 1987 produced fewer than 100 positive results).55 Such a time
lag is exactly what the HIV theory predicts, because most people are expected to live with HIV for
some time before developing AIDS.

Thailand is not unique. Exactly the same pattern can be seen in statistics worldwide, from Albania
(where HIV and AIDS are both very rare) to Zimbabwe (where AIDS case reports soared during 1987-95,
following the trend in HIV prevalence).56 57

This trend can also be seen within individual countries as regions, cities or population groups with
higher HIV prevalence report a higher rate of AIDS.58

How well does HIV infection predict illness and death?
A mountain of evidence shows that much can be predicted from a positive test result. For example:

At least half of people develop AIDS-defining conditions within 10 years of HIV infection, if they
don't take antiretroviral drugs. Only a few do not develop AIDS within 20 years.59 60
HIV-positive Americans and Canadians are over 1,000 times more likely to develop AIDS-defining
diseases (such as PCP and Kaposi's sarcoma) than those who test negative.61 62
A study in Uganda found that HIV-positive people were 16 times more likely to die over five years
than those who tested negative. For those aged 25-34 years old, HIV infection raised the death rate
by a factor of 27.63 Numerous other studies have found similar results in Tanzania, Malawi, Rwanda
and other parts of Africa.64 65 66 67
A study of female sex workers in Thailand found the death rate to be over 50 times greater among
those who tested positive. All of the positive women died of conditions associated with immune
deficiency, compared with none of the negative women.68
During a 16-year, large-scale monitoring study of homosexual and bisexual men in the US, 60% of
HIV-positives died compared with 2.3% of HIV-negatives.69
In the UK between 1979 and 1992, death rates increased massively among HIV-positive haemophiliacs,
but remained unchanged among the rest.70 Similar research in the USA found that HIV-positive
haemophiliacs were 11 times more likely to die over a ten-year period, compared with those who tested
negative.71
In a European study of babies born to HIV-positive women, none of those who tested negative developed
AIDS, compared to 30% of those who tested positive. By their first birthday, 17% of the HIV-positive
babies had died.72 A similar study in Uganda found that more than half of HIV-positive babies died
before their second birthdays, compared to one sixth of those who were HIV-negative.73
Alternative theories cannot explain why HIV tests should be so effective at predicting illness and
death in so many diverse groups of people from all parts of the world.

It is even possible to predict the likelihood that someone will soon develop AIDS by measuring the
amount of HIV in their blood, which is known as "viral load". Such measurements can be made using
PCR, branched-DNA signal-amplification (bDNA) or quantitative microculture techniques. For example,
the table below - based on a long term study of 1,604 patients - illustrates just how useful bDNA
forecasts can be:74

Viral load (RNA copies per millilitre of blood plasma) Proportion of patients developing AIDS within
six years
less than 500 5.4%
501-3,000 16.6%
3,001-10,000 31.7%
10,001-30,000 55.2%
more than 30,000 80.0%

Dr Kary Mullis, who invented the PCR process, has questioned its ability to measure viral load.
However, his arguments have been theoretical, and are not backed up by large-scale surveys, which
have repeatedly shown a clear association between viral load and progression to AIDS (in all parts of
the world).75 76 Dr Mullis' objections do not apply to the unrelated bDNA and quantitative
microculture techniques. Modern bDNA tests produce very similar viral load counts to modern PCR tests
(though this was less true of some earlier models).77 78 As with antibody tests, there is no
convincing alternative explanation for why viral load counts should be such useful indicators.

Effective drug treatments
The first drug licensed for fighting HIV was zidovudine, better known as AZT, which gained approval
in 1987. Multiple studies found that AZT reduced opportunistic infections and increased CD4+ cell
counts and survival among people with AIDS. However, the positive effects of AZT did not last very
long, and a major investigation known as the Concorde Study found that people who started taking the
drug at an early stage of HIV infection, before the onset of symptoms, received little or no
long-term benefit (though neither did they fare any worse).79 80 81

Since the mid-1990s, other types of anti-HIV drugs have also been available, including protease
inhibitors, which were designed specifically to target HIV proteins.82 It has been found that when
different drugs are taken together, they bring much longer-lasting benefits than AZT alone.

Numerous large-scale, controlled studies have consistently shown that the right combination of drugs
can dramatically reduce incidence of AIDS and death. One drug is better than none, and two is better
than one, but a combination of three drugs (from two different classes) is much better still.
Virologists explain that this is because HIV finds it a lot harder to evolve resistance to several
drugs at the same time. Modern three-drug combinations reduce the risk of AIDS and death by over
80%.83 84 85 86

Many recent studies in Africa have found that treatment is just as effective there as it is in Europe
and America.87

In most people, the drugs cause a sharp fall in viral load. However, some patients do not experience
such an effect, and these people are far more likely to develop AIDS or to die. This fact in itself
very strongly suggests that HIV causes AIDS.88

HIV and AIDS in the United Kingdom, 1988-2002The benefits of more effective drug treatments can be
seen in national statistics from rich countries in which most people have had access to them. On the
right is a graph of HIV diagnoses, AIDS diagnoses and AIDS deaths in the UK between 1988 and 2002.
This graph shows that the numbers of AIDS diagnoses and deaths fell by more than half between the end
of 1995 and the end of 1998. This trend followed the widespread introduction of combination
therapy.89

Similar patterns can be seen in statistics from other European countries, Canada, Australia and the
USA.90 However, it should be noted that American statistics were distorted during the period
1990-1996 because of a major expansion in the AIDS surveillance case definition in 1993. For the
first time, people could be diagnosed with AIDS on the basis of a low CD4+ cell count. The majority
of these people would have gone on to develop AIDS-defining diseases before death, so would have been
included in the statistics anyway, but the change in definition meant they were diagnosed earlier,
and this skewed the statistics.

The distortion caused by the change in definition was temporary, and cannot account for the major
declines in AIDS diagnoses and deaths that occurred in the USA during the late 1990s. Nor can the
declines be explained by trends in HIV incidence.91 92 93 94 Incidence of AIDS-defining infections
like PCP rose during the early 1990s and then decreased significantly between 1995 and 1998.95 96

The ability of antiretroviral drugs to prevent mother-to-child HIV transmission has been demonstrated
around the world.97 Following the widespread introduction of these drugs during pregnancy, the number
of reported AIDS cases among American children has fallen to around 100 per year, compared to nearly
1,000 per year in the early 1990s.98

Antiretroviral therapy, alongside treatment for opportunistic infections, is thought to have saved at
least three million years of life in the USA alone.99

Drug abuse and other factors
Dissidents who claim that HIV does not cause AIDS have felt compelled to come up with alternative
causes. These generally include recreational drugs (including heroin, cocaine, amphetamines and
nitrite inhalants known as "poppers"), malnutrition, lack of clean drinking water, clotting factors
used in blood transfusions, and anti-HIV drugs such as AZT. Some groups also suggest semen, "immune
overload", antibiotics, benzene, stress, or lack of sleep.

In the early 1980s, when only a small number of AIDS cases had been reported, the medical
establishment gave some of these possible causes very serious consideration. But such theories
quickly lost favour as more cases emerged among men, women and children who did not fit the
established risk groups, and it was established that affected people had been exposed to the bodily
fluids of other affected people.100 Epidemiological data pointed to an infectious cause before HIV
was ever isolated.101

Today, most scientists agree that controlled studies of drug users, heterosexuals, homosexuals,
haemophiliacs and twin babies have consistently shown that HIV is the only factor that predicts who
will develop AIDS. Associations in time and place between trends in drug use or promiscuity and
trends in AIDS diagnoses are considered much too weak to prove causation.102 103

Dr Duesberg has claimed that some HIV-negative drug users have developed AIDS-like immune
abnormalities and diseases. But his definition of "AIDS-like" is very vague, and none of these cases
would merit an AIDS diagnosis.104 105 106

Antiretroviral drugs can have toxic side effects. However, there is no evidence that anti-HIV drugs
cause the severe immune deficiency typical of AIDS, and there is abundant evidence that currently
recommended courses of antiretroviral therapy can improve the length and quality of life of
HIV-positive people.107 108 109 110

Certain AIDS-related diseases are more common among some population groups than among others. This is
not surprising, and it does not mean that they cannot all have the same underlying cause.111 112

Severe malnutrition is a known cause of immune deficiency (though not the specific type of immune
deficiency that is characteristic of AIDS). That is why all definitions of AIDS specify that there
must be no evidence of severe malnutrition. Poor nutrition is also thought to make people with HIV
more vulnerable to illness, so improving diet is an essential component of programmes to help
HIV-infected people around the world. Still, such actions are not by themselves sufficient, because
thousands of Africans who are well fed and cared for continue to die from AIDS. As the next section
explains, there is no evidence that deterioration in diet or living standards can explain AIDS in
Africa, which appears to be a totally new epidemic disease.

AIDS in Africa
Some dissidents claim there is no great new AIDS epidemic in Africa, just the same old diseases
caused by poverty, hunger and poor sanitation. They say that official statistics are misleading
because AIDS in Africa may be diagnosed on the basis of various clinical symptoms without an HIV test
if none is available.113 We'll challenge these claims using four lines of argument.

Firstly, medical records from a number of African countries show marked increases in a number of
AIDS-related diseases during the late 1970s and early 1980s. These records suggest that AIDS was
probably rare or non-existent before that time.114

Secondly, as discussed above, numerous studies have found that people who test positive for HIV face
a much higher risk of illness and death. Surveillance studies show that HIV prevalence rates have
soared across sub-Saharan Africa since the early 1980s, and are now extremely high. It is therefore
reasonable to estimate that millions are ill and dying.115

Thirdly, since the early 1980s, African countries with high HIV prevalence have suffered increased
burdens of disease and death, as measured by censuses and surveys. For example:

Between the 1980s and mid 1990s, adult death rates rose significantly in countries where HIV had been
widespread for many years (such as Uganda, Zambia and Zimbabwe), but not in countries where rates had
been lower.116 117
Increases in death and disease have disproportionately affected young and middle-aged adults,
especially those living in urban areas. Relatively well-paid professionals including teachers and
doctors have been among the worst hit. This pattern is not typical of diseases caused by malnutrition
or dirty water, which generally target the poor and the elderly.118 119 120
In several countries, the number of orphans has risen so dramatically that communities can no longer
cope, and child-headed households are now commonplace. Such changes indicate that sexually active
adults are dying while children (and the elderly) are surviving. Household surveys have revealed a
strong correlation between rates of orphanhood and adult HIV prevalence.121 122 123
Patterns of disease have changed. For example, rates of Kaposi's sarcoma have soared,124 and
tuberculosis - which was once confined to the poor, the weak and the elderly - today kills numerous
well-fed Africans in the prime of life.125 126
Not all of sub-Saharan Africa has been equally affected by the recent changes. For example, Southern
Africa has suffered much more than Western Africa, even though the regions have experienced similarly
high levels of extreme poverty, malaria, food shortages and conflict. The only factor associated with
the changes is HIV prevalence.127 128

Fourthly, the number of reported AIDS cases has risen across sub-Saharan Africa. Experts believe
these statistics vastly underestimate the scale of the epidemics because the reporting systems are
inadequate. This inadequacy is partly due to frequent misdiagnosis (compounded by AIDS-related
stigma), but is mostly due to poor infrastructure and lack of access to healthcare. In addition, the
quality of the reporting systems varies from one country to another. Nevertheless, it is possible to
spot two clear patterns in the data.

The first obvious trend is that the number of reported AIDS cases increased everywhere during the
1980s. As in all other parts of the world, this increase followed a rise in HIV prevalence. The
second trend concerns the number of AIDS cases reported per million of population. In general, the
highest rates have been recorded by Southern African countries where HIV has been widespread for many
years, while the lowest rates tend to come from Western African countries with historically much
lower HIV prevalence. The lowest AIDS rate of all is reported by the island nation of Madagascar,
where until recently HIV was extremely rare.129

The only major exception to the pattern in AIDS case rates is South Africa, which has reported
relatively low figures. However, HIV prevalence did not reach very high levels in South Africa until
the mid-1990s, several years later than in nearby countries such as Zambia and Zimbabwe. In addition,
South Africa stopped reporting AIDS cases to the World Health Organisation in 1996, before most other
African countries, and before the rise in HIV had had a chance to take effect.130

Compelling evidence of the impact of AIDS in South Africa since that time comes from studies of death
certificates. These show that the annual number of reported deaths (from all causes) rose by 79%
between 1997 and 2004. Among those aged 25-49 years old, the increase was 161%.131 Rates of death
from AIDS-related conditions increased according to a distinctive age distribution, which peaked
among the age groups 0-4 and 25-49 years. Other conditions showed no such pattern. The estimated
number of AIDS deaths based on these data is similar to estimates based on HIV prevalence.132

What we don't know
There are still a few things we don't know about HIV and AIDS.

For example, we don't really know why both HIV and AIDS have become generally common in some African
countries but not in Europe or the US - though we do have some theories. Contributing factors include
the much higher prevalence of untreated sexually transmitted diseases in Africa (which greatly
increase the chances of HIV transmission) and, quite possibly, differences between HIV subtypes. In
addition, people who have poorer general health (including those who have malaria or tuberculosis)
tend to have more HIV in their bodily fluids, which makes them more likely to transmit the virus.

Different patterns of sexual networking also have an effect. Viral loads are especially high during
the first few weeks after infection, so the risk of transmission is then much higher. This means that
people who have several concurrent sexual partners are able to spread the virus very efficiently
before they test positive or fall ill. Studies suggest that, even though Africans do not report more
sexual partners over a lifetime than other populations, concurrent partnerships are more common in
Africa and most common in Southern Africa.

Due to lack of access to HIV testing and treatment, as well as educational and cultural factors, the
vast majority of Africans do not know their HIV status, and many people, especially women, find it
very difficult to adopt strategies that would lower their risk of becoming infected or of infecting
others. High levels of mobility, particularly of migrant workers, can also help to spread HIV.133 134
135 136 137 138

The concentration of an infectious disease among particular groups is not unusual. Hepatitis B is
transmitted via much the same routes as HIV, and in Western countries it has similar risk groups.
Hepatitis C (which is primarily spread via blood) is largely confined to injecting drug users, and
recent increases in syphilis (usually sexually transmitted) have been fuelled by outbreaks among men
who have sex with men. Surveillance statistics from throughout the Western world show that AIDS is
becoming increasingly common outside the traditional risk groups, following a similar trend in HIV
cases. In 2003, around a third of new American AIDS diagnoses, and two-thirds of those among women,
occurred among non-drug using heterosexuals.139 Epidemiological evidence of male-to-female,
male-to-male and female-to-male sexual transmission of HIV is abundant.140

Something else we don't fully understand is how HIV causes AIDS. Again, however, we do have some
theories, which explain how the virus might be able to stop the immune system working properly in a
number of ways, not just by directly killing cells.141 Ignorance about precisely how something
happens is not proof that it does not happen.

Conclusion
There is no single scientific paper that proves HIV causes AIDS. Instead there are tens of thousands
of papers containing a wide range of evidence that, taken together, make the case overwhelming.

People should be encouraged to question scientific orthodoxy. However, the views of AIDS dissidents,
which have been well known for many years and thoroughly debated in scientific journals, have failed
to win support. The core arguments of the Perth Group (that HIV has not been isolated according to
their own particular rules) and Dr Duesberg (that no one fully understands how HIV causes AIDS) do
not invalidate the wide range of evidence outlined on this page. The HIV theory is compelling because
it provides a simple, unique cause that consistently accounts for all of the observed phenomena.

As an independent AIDS organisation, AVERT is primarily interested in what works. Studies have
repeatedly shown that antibody testing is a highly effective way of predicting risk for AIDS; that
modern antiretroviral treatment brings dramatic benefits; and that people who avoid exposure to HIV
do not get AIDS. We will therefore continue wholeheartedly to recommend these things.

Main sources
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Syndrome", NIH, 1995
AIDSTruth.org - The Scientific Evidence for HIV/AIDS
VirusMyth.net
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CDC "What causes AIDS?", updated December 2003
Duesberg.com
ThePerthGroup.com
The most prominent dissident groups are The HEAL network, Alive and Well and ACT UP San Francisco
(not affiliated with other ACT UP chapters, who believe that HIV causes AIDS)
See AVERT's first history page
CDC "Current Trends Update on Acquired Immune Deficiency Syndrome (AIDS) --United States", September
1982
For a historical overview of US AIDS definitions, see "Answering the AIDS Denialists: Is AIDS Real?",
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This interpretation of Koch's Postulates is preferred by Dr Duesberg
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See AVERT's history pages
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For example: Salahuddin 1985, Ho 1985, Wofsy 1986, Hollander 1987, Geier 1992
For example: Briggs 2003, Schwedler 2003, McDonald 2002, Benjamin 2005, Reil 1998, Zhu 2006
For images from sucrose density gradients see Gluschankof 1997 and Bess 1997, as well as commentary
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For example: Fang 1996, Feng 1998, Carr 1999, Ling 2000, Oelrichs 2000, Laukkanen 2000, Philpott 2005
Los Alamos HIV Sequence Database
See AVERT's HIV subtypes page
"Koch's Postulates Fulfilled", NIH, 1995
See AVERT's Deliberate, Reckless and Accidental Transmission page
For example: Takahoko 2001, Mukai 2002, Tebit 2004, Shi 2004, Grisson 2004, Kusagawa 2002, Chen 1997
ThePerthGroup.com
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See "Missing virus" for the series of exchanges that followed Dr Duesberg's claim, from 1996 onwards
A very long series of correspondence between the Perth Group, other dissidents and supporters of the
HIV theory can be found in the BMJ debate sparked by an article by Fassin and Schneider, from
February 2003 onwards
"Reasons for Decision of The Honourable Justice Sulan", R v PARENZEE [2007] SASC 143, Supreme Court
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UNAIDS/WHO Epidemiological Fact Sheets, 2004 edition
"The Epidemic in Thailand", Cohen, Science 266, December 1994
UNAIDS/WHO Epidemiological Fact Sheets, 2004 edition
"Seroprevalence Surveys", NIH, 1995
See AVERT's statistics section for some examples
"Course of HIV Infection", NIH, 1995
"HIV-1 infection in rural Africa: is there a difference in median time to AIDS and survival compared
with that in industrialized countries?", Morgan et al, AIDS 16(4), 8 March 2002
"MACS and WHIS Studies Provide Overwhelming Evidence That HIV Cause AIDS", NIH, 2000
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serological studies", Porter and Zaba, AIDS 18(suppl 2), June 2004
"Child mortality and HIV infection in Africa: a review", Newell et al, AIDS 18(suppl 2), June 2004
"Mortality impact of the AIDS epidemic: evidence from community studies in less developed countries",
Boerma et al, AIDS 12 Supplement 1, 1998
For example: Borgdoff 1995, Taha 1999, Spira 1999, Leroy 1995, Ackah 1995, Thea 1993, Madhi 2000, Zwi
2000, Sewankambo 2000, Corbett 2002
"High mortality among women with hiv-1 infection in Thailand", Kilmarx, The Lancet 356(9231), August
2000
"The Evidence That HIV Causes AIDS", NIH factsheet, revised February 2003
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Haemophilia Centre Directors' Organisation", Darby et al, Nature 377(6544), September 1995
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"Children born to women with HIV-1 infection: natural history and risk of transmission. European
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Uganda, Brahmbhatt et al, Journal of AIDS 41(4), April 2006
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Intern Med 126(12), June 1997
For example: Palumbo 1998, Taha 2000, Pantaleo 1995, Cao 1995, Barker 1998, Hansmann 2005
"Answering the AIDS Denialists: CD4 (T-Cell) Counts, and Viral Load", Mirken, AIDS Treatment News,
April 2000
"Comparative evaluation of the QUANTIPLEX HIV-1 RNA 2.0 and 3.0 (bDNA) assays and the AMPLICOR HIV-1
MONITOR v1.5 test for the quantitation of human immunodeficiency virus type 1 RNA in plasma",
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symptom-free HIV infection", Concorde Coordinating Committee, The Lancet 343(8902, April 1994
"AZT and AIDS", NIH, 1995
"Could Drugs, Rather Than a Virus, Be the Cause of AIDS?", Cohen, Science 266, December 1994
For a guide to the different types of drugs, see AVERT's Introduction to treatment page
For example in the US and Canada: Palella 1998, Detels 1998, Hogg 1999, Schwarz 2000, McNaghten 2000
For example in Europe: Mocroft 1998, Mocroft 2000, de Martino 2000, CASCADE 2000, Porter 2003, Tassie
2002, Ormaasen 2007
'Systematic review and meta-analysis of evidence for increasing numbers of drugs in antiretroviral
combination therapy', Jordan et al, BMJ 324(7340), 30 March 2002
"AIDS Treatment Improves Survival: Answering the 'AIDS Denialists'", Mirken, AIDS Treatment News,
September 2000
For example: Fassinou 2004, Laurent 2005, Flanigan 2005, Ivers 2005, Djomand 2003, Wester 2005,
Wools-Kaloustian 2006
For example: Montaner 1998, Palumbo 1998, O'Brien 1996, Katzenstein 1996, Marschner 1998, Hammer
1997, Cameron 1998, Ledergerber 1999
"HPA Communicable Disease Surveillance Centre (HIV and STI Department) and the Scottish Centre for
Infection and Environmental Health: Unpublished Quarterly Surveillance Tables"
See AVERT's statistics section
"Current Trends Update: Impact of the Expanded AIDS Surveillance Case Definition for Adolescents and
Adults on Case Reporting -- United States, 1993", MMWR 43(09), March 1994
"HIV in the United States at the Turn of the Century: An Epidemic in Transition", Karon et al,
American Journal of Public Health 91(7), July 2001
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et al, J Infect Dis 179(3), 1999 March
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September 2000
"Current Trends Update: Trends in AIDS Diagnosis and Reporting Under the Expanded Surveillance
Definition for Adolescents and Adults - United States, 1993", MMWR 43(45), November 1994
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States in the era of highly active antiretroviral therapy", Kaplan et al, Clin Infect Dis 30 Suppl 1,
April 2000
For example: Connor 1994, Cooper 1996, Fiscus 1996, Shaffer 1999, Fiscus 2002, Harris 2002, Cooper
2002, Moodley 2003
Centers for Disease Control and Prevention. HIV/AIDS Surveillance Report 2003, (Vol. 15).
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with Challenges", Vermund, Journal of Infectious Diseases 194(1), 1 July 2006
"Initial Theories", NIH, 1995
"Epidemiologic Notes and Reports Immunodeficiency among Female Sexual Partners of Males with Acquired
Immune Deficiency Syndrome (AIDS) -- New York", MMWR 31(52), January 1983
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Syndrome", NIH, 1995
"The Duesberg Phenomenon", Cohen, Science 266, December 1994
"Could Drugs, Rather Than a Virus, Be the Cause of AIDS?", Cohen, Science 266, December 1994
"The AIDS Heresies", Harris, 1995
"AIDS and Injection Drug Users", NIH, 1995
"AZT and AIDS", NIH, 1995
"Could Drugs, Rather Than a Virus, Be the Cause of AIDS?", Cohen, Science 266, December 1994
For example: Palella 1998, Mocroft 1998, Mocroft 2000, Detels 1998, de Martino 2000, CASCADE 2000,
Hogg 1999, Schwarz 2000, McNaghten 2000
"AIDS Treatment Improves Survival: Answering the 'AIDS Denialists'", Mirken, AIDS Treatment News,
September 2000
"Answering the AIDS Denialists: Is AIDS Real?", Mirken, AIDS Treatment News, December 2000
"Treating Opportunistic Infections Among HIV-Infected Adults and Adolescents", CDC, December 2004
For more about AIDS definitions see WHO "Overview of Internationally Used HIV/AIDS Case Definitions"
See AVERT's first history page
UNAIDS/WHO 2004 Report on the global AIDS epidemic
"Impact of the HIV epidemic on mortality in sub-Saharan Africa: evidence from national surveys and
censuses", Timaeus, AIDS 12(suppl 1), 1998
"The impact of AIDS on adult mortality: evidence from national and regional statistics", Blacker,
AIDS 18(suppl 2), June 2004
"The Impact of AIDS", United Nations, 2004
"The World Health Report 2004", WHO, 2004
"The impact of AIDS on adult mortality: evidence from national and regional statistics", Blacker,
AIDS 18(suppl 2), June 2004
"The Impact of AIDS", United Nations, 2004
"Children on the Brink 2004", UNAIDS, 2004
For example: Monasch 2004, Grassly 2005, Watts 2005, Makumbi 2005
For example: Bayley 1991, Wabinga 1993, Wabinga 2000, Chokunonga 1999, Athale 1995, Sitas 2001
For example: Harries 1997, Floyd 1999, Cantwell 1997, Glynn 2004
"Global Tuberculosis Control: Surveillance, Planning, Financing, WHO Report 2004", World Health
Organization
"The Impact of AIDS", United Nations, 2004
"The World Health Report 2004", WHO, 2004
Data derived from UNAIDS/WHO Epidemiological Fact Sheets, 2004 edition, and UN population estimates
for the year 2000
Data derived from UNAIDS/WHO Epidemiological Fact Sheets, 2004 edition, and UN population estimates
for the year 2000
"Mortality and causes of death in South Africa, 2003 and 2004", Statistics South Africa, May 2006
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191(9), May 2005
"HIV and sexually transmitted diseases: lethal synergy", Cohen, Top HIV Med 12(4), October-November
2004
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Infect Dis 189(10), May 2004
"Concurrent sexual partnership help to explain Africa's high HIV prevalence: implications for
prevention", Halperin and Epstein, The Lancet 364(9428), July 2004
"The spread and effect of HIV-1 infection in sub-Saharan Africa", Buve et al, The Lancet 359(9322),
June 2002
"The AIDS Heresies", Harris, 1995
CDC HIV/AIDS Surveillance Report 2003, (Vol. 15)
"Safer-sex methods", HIV InSite Knowledge Base Chapter, content reviewed January 2006
"How HIV Causes AIDS", NIH Fact Sheet, revised November 2004
Last updated June 26, 2007