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HIV Causes AIDS

back to top HIV is the cause of AIDS

"AIDS is caused by infection with a virus called human immunodeficiency virus (HIV)."1

This is the standard explanation of what causes AIDS. But what evidence do scientists have to support the fact that HIV causes AIDS? 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.

back to top Who doubts that HIV causes AIDS?

By far the most significant scientist to question the fact that HIV is the cause of AIDS 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 and 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.

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.

back to top What is AIDS?

Before we can begin to look for a cause for AIDS, 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

back to top 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.

back to top 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

back to top 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 and urine, 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 32

Techniques developed in the mid-1990s have made it much easier to extract and sequence the complete genetic material (genome) of an isolated virus.33 34 The Los Alamos database now contains hundreds of full-length HIV genomes from around the world, each containing the same nine genes.35 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.36

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.37 People who have been exposed to the same source of infection contain genetically very similar HIV strains – similar enough for court convictions.38

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.39

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.40

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.41 42 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.43 44 45

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."46

back to top 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.47

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.48 In some studies, chimpanzees deliberately infected with HIV-1 have gone on to develop AIDS-like conditions (though this appears to be rare),49 while HIV-2 has had the same effect on baboons.50 Macaque monkeys have developed AIDS after being infected with a hybrid virus called SHIV, which contains genes taken from HIV.51 And in mice engineered to have a human immune system, HIV produces the same patterns of disease as in humans.52

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.53

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.54

back to top 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, 1984-2000HIV 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 2000.55

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).56 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).57 58

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.59

back to top 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:

  • Around 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.60 61
  • 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.62 63
  • 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 27.64 Numerous other studies have found similar results in Tanzania, Malawi, Rwanda and other parts of Africa.65 66 67 68
  • 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.69
  • 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.70
  • In the UK between 1979 and 1992, death rates increased massively among HIV-positive haemophiliacs, but remained unchanged among the rest.71 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.72
  • 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.73 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.74

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:75

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).76 77 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).78 79 As with antibody tests, there is no convincing alternative explanation for why viral load counts should be such useful indicators.

back to top 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).80 81 82

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.83 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%.84 85 86 87

Many recent studies in Africa have found that treatment is just as effective there as it is in Europe and America.88 A study that analysed demographic data from KwaZulu Natal in South Africa found a strong link between the decline in mortality, particularly among young adults, and the decline in HIV-related mortality following the introduction of the nationwide antiretroviral therapy programme.89

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.90

HIV and AIDS in the United Kingdom, 1988-2002HIV and AIDS in the United Kingdom, 1988-2002

The 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.91

Similar patterns can be seen in statistics from other European countries, Canada, Australia and the USA.92 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.93 94 95 96 Incidence of AIDS-defining infections like PCP rose during the early 1990s and then decreased significantly between 1995 and 1998.97 98

The ability of antiretroviral drugs to prevent mother-to-child HIV transmission has been demonstrated around the world.99 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.100

Antiretroviral therapy, alongside treatment for opportunistic infections, is thought to have saved at least three million years of life in the USA alone.101

back to top 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.102 Epidemiological data pointed to an infectious cause before HIV was ever isolated.103

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.104 105

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.106 107 108

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.109 110 111 112

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.113 114

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.

back to top 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.115 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.116

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.117 118

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.119 120
  • 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.121 122 123
  • In several countries with a high HIV prevalence, the number of orphans has risen dramatically. 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.124 125 126
  • Patterns of disease have changed. For example, rates of Kaposi's sarcoma have soared,127 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.128 129

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.130 131

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.132

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.133

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%.134 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.135

back to top 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.

Nominet Winner 2012

Sources back to top

References back to top

  1. CDC "What causes AIDS?", updated December 2003
  2. Duesberg.com
  3. ThePerthGroup.com
  4. 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)
  5. See AVERT's first history page
  6. CDC "Current Trends Update on Acquired Immune Deficiency Syndrome (AIDS) --United States", September 1982
  7. For a historical overview of US AIDS definitions, see "Answering the AIDS Denialists: Is AIDS Real?", Mirken, AIDS Treatment News, December 2000
  8. WHO "Overview of Internationally Used HIV/AIDS Case Definitions"
  9. CDC "1993 Revised Classification System for HIV Infection and Expanded Surveillance Case Definition for AIDS Among Adolescents and Adults"
  10. "Natural history and mortality in HIV-positive individuals living in resource-poor settings: A literature review", Schneider et al, June 2004
  11. "Short-term risk of AIDS according to current CD4 cell count and viral load in antiretroviral drug-naive individuals and those treated in the monotherapy era", CASCADE Collaboration, AIDS 18(1), 2 January 2004
  12. "Short-term risk of AIDS or death in people infected with HIV-1 before antiretroviral therapy in South Africa: a longitudinal study", Badri et al, The Lancet 368(9543), 7-13 October 2006
  13. "The AIDS Heresies", Harris, 1995
  14. "Answering the AIDS Denialists: CD4 (T-Cell) Counts, and Viral Load", Mirken, AIDS Treatment News, April 2000
  15. This interpretation of Koch's Postulates is preferred by Dr Duesberg
  16. "Koch's postulates and the etiology of AIDS: an historical perspective", Harden, 1992
  17. "Unexplained Opportunistic Infections and CD4+ T-Lymphocytopenia without HIV infection - An Investigation of Cases in the United States", Smith et al, NEJM 328(6), February 1993
  18. "The Immunological Profile of People with AIDS", NIH, 1995
  19. "The AIDS Heresies", Harris, 1995
  20. "Could Drugs, Rather Than a Virus, Be the Cause of AIDS?", Cohen, Science 266, December 1994
  21. UNAIDS/WHO Questions and Answers, November 2004
  22. "The Evidence That HIV Causes AIDS", NIH factsheet, revised February 2003
  23. "Factors Known to Cause False Positive HIV Antibody Test Results", Johnson, September/October 1996
  24. "Revised Guidelines for HIV Counseling, Testing and Referral", CDC, November 2001
  25. "HIV Testing 101 (Part 2 of 2)", Mirken, AIDS Treatment News, November 2001
  26. Department of Health (2004) "National HIV and Syphilis Antenatal Sero-prevalence Surveys in South Africa"
  27. See AVERT's history pages
  28. NIH (1995) 'The Relationship Between The Human Immunodeficiency Virus'
  29. For example: Salahuddin 1985, Ho 1985, Wofsy 1986, Hollander 1987
  30. For example: Briggs 2003, Schwedler 2003, McDonald 2002, Benjamin 2005, Reil 1998, Zhu 2006
  31. For images from sucrose density gradients see Gluschankof 1997 and Bess 1997, as well as commentary in Dettenhofer 1999, Trubey 2003 and Welker 2000
  32. Hübner, W et al (2009) 'Quantitative 3D video microscopy of HIV transfer across T cell virological synapses', Science, 27 March 2009, 323: 1743-1747
  33. "Recovery of virtually full-length HIV-1 provirus of diverse subtypes from primary virus cultures using the polymerase chain reaction", Salminen et al, Virology, 1995
  34. For example: Fang 1996, Feng 1998, Carr 1999, Ling 2000, Oelrichs 2000, Laukkanen 2000, Philpott 2005
  35. Los Alamos HIV Sequence Database
  36. See AVERT's HIV subtypes page
  37. NIH (1995) 'The Relationship Between The Human Immunodeficiency Virus'
  38. See AVERT's Criminal Transmission of HIV
  39. For example: Takahoko 2001, Mukai 2002, Tebit 2004, Shi 2004, Grisson 2004, Kusagawa 2002, Chen 1997
  40. ThePerthGroup.com
  41. "HIV, AIDS, and the Distortion of Science", Coon, August 2000
  42. "ISOLATED FACTS ABOUT HIV: A response to claims by AIDS dissidents that HIV doesn't exist", King, April 1996
  43. "Duesberg Defends Challenges to the Existence of HIV: Article 1 of 2 for Continuum", Duesberg, July/August 1996
  44. See "Missing virus" for the series of exchanges that followed Dr Duesberg's claim, from 1996 onwards
  45. 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
  46. "Reasons for Decision of The Honourable Justice Sulan", R v PARENZEE [2007] SASC 143, Supreme Court of South Australia, 17 April 2007
  47. NIH (1995) 'The Relationship Between The Human Immunodeficiency Virus'
  48. NIH (1995) "Evidence from Animal and Laboratory Models"
  49. "Progressive infection in a subset of HIV-1-positive chimpanzees", O'Neil et al, J Infect Dis 182(4), October 2000
  50. "Human immunodeficiency virus-2 infection in baboons is an animal model for human immunodeficiency virus pathogenesis in humans", Locher et al, Arch Pathol Lab Med 122(6), June 1998
  51. "Chimeric simian/human immunodeficiency virus that causes progressive loss of CD4+ T cells and AIDS in pig-tailed macaques", Joag et al, J Virol 70(5), May 1996
  52. "The SCID-hu mouse as a model for HIV-1 infection", Nature 363(6431), June 1993
  53. NIH (1995) 'The Relationship Between The Human Immunodeficiency Virus'
  54. "HIV causes AIDS: Koch's postulates fulfilled", O'Brien and Goedert, Current Opinion in Immunology 8(5), October 1996
  55. UNAIDS/WHO Epidemiological Fact Sheets, 2004 edition
  56. "The Epidemic in Thailand", Cohen, Science 266, December 1994
  57. UNAIDS/WHO Epidemiological Fact Sheets, 2004 edition
  58. "Seroprevalence Surveys", NIH, 1995
  59. See AVERT's statistics section for some examples
  60. "Time from HIV-1 seroconversion to AIDS and death before widespread use of highly-active antiretroviral therapy: a collaborative re-analysis. Collaborative Group on AIDS Incubation and HIV Survival including the CASCADE EU Concerted Action. Concerted Action on SeroConversion to AIDS and Death in Europe.", The Lancet 355(9210), 1 April 2000
  61. "Time from HIV seroconversion to death: a collaborative analysis of eight studies in six low and middle-income countries before highly active antiretroviral therapy", Todd et al, AIDS 21 (suppl 6), November 2007
  62. "MACS and WHIS Studies Provide Overwhelming Evidence That HIV Cause AIDS", NIH, 2000
  63. "HIV-1 and the aetiology of AIDS", Schechter et al, The Lancet 341(8846), March 1993
  64. "Mortality associated with HIV-1 infection over five years in a rural Ugandan population: cohort study", Nunn et al, BMJ 315(7111), September 1997
  65. "The empirical evidence for the impact of HIV on adult mortality in the developing world: data from serological studies", Porter and Zaba, AIDS 18(suppl 2), June 2004
  66. "Child mortality and HIV infection in Africa: a review", Newell et al, AIDS 18(suppl 2), June 2004
  67. "Mortality impact of the AIDS epidemic: evidence from community studies in less developed countries", Boerma et al, AIDS 12 Supplement 1, 1998
  68. For example: Borgdoff 1995, Taha 1999, Spira 1999, Leroy 1995, Ackah 1995, Thea 1993, Madhi 2000, Zwi 2000, Sewankambo 2000, Corbett 2002
  69. "High mortality among women with hiv-1 infection in Thailand", Kilmarx, The Lancet 356(9231), August 2000
  70. "The Evidence That HIV Causes AIDS", NIH factsheet, revised February 2003
  71. "Mortality before and after HIV infection in the complete UK population of haemophiliacs. UK Haemophilia Centre Directors' Organisation", Darby et al, Nature 377(6544), September 1995
  72. "Mortality and haemophilia", Goedert, The Lancet 346(8987), November 1995
  73. "Children born to women with HIV-1 infection: natural history and risk of transmission. European Collaborative Study", The Lancet 337(8736), February 1991
  74. "Mortality in HIV-Infected and Uninfected Children of HIV-Infected and Uninfected Mothers in Rural Uganda, Brahmbhatt et al, Journal of AIDS 41(4), April 2006
  75. "Plasma viral load and CD4+ lymphocytes as prognostic markers of HIV-1 infection", Mellors et al, Ann Intern Med 126(12), June 1997
  76. For example: Palumbo 1998, Taha 2000, Pantaleo 1995, Cao 1995, Barker 1998, Hansmann 2005
  77. "Answering the AIDS Denialists: CD4 (T-Cell) Counts, and Viral Load", Mirken, AIDS Treatment News, April 2000
  78. "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", Anastassopoulou et al, J Virol Methods 91(1), January 2001
  79. "Comparative evaluation of the Cobas Amplicor HIV-1 Monitor Ultrasensitive Test, the new Cobas AmpliPrep/Cobas Amplicor HIV-1 Monitor Ultrasensitive Test and the Versant HIV RNA 3.0 assays for quantitation of HIV-1 RNA in plasma samples", Berger et al, J Virol Methods 33(1), May 2005
  80. "Concorde: MRC/ANRS randomised double-blind controlled trial of immediate and deferred zidovudine in symptom-free HIV infection", Concorde Coordinating Committee, The Lancet 343(8902, April 1994
  81. "AZT and AIDS", NIH, 1995
  82. "Could Drugs, Rather Than a Virus, Be the Cause of AIDS?", Cohen, Science 266, December 1994
  83. For a guide to the different types of drugs, see AVERT's Introduction to treatment page
  84. For example in the US and Canada: Palella 1998, Detels 1998, Hogg 1999, Schwarz 2000, McNaghten 2000
  85. For example in Europe: Mocroft 1998, Mocroft 2000, de Martino 2000, CASCADE 2000, Porter 2003, Tassie 2002, Ormaasen 2007
  86. '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
  87. "AIDS Treatment Improves Survival: Answering the 'AIDS Denialists'", Mirken, AIDS Treatment News, September 2000
  88. For example: Fassinou 2004, Laurent 2005, Flanigan 2005, Ivers 2005, Djomand 2003, Wester 2005, Wools-Kaloustian 2006
  89. UNAIDS/UNICEF/WHO (2010) 'Towards universal access: Scaling up priority HIV/AIDS interventions in the health sector, Progress Report 2010'
  90. For example: Montaner 1998, Palumbo 1998, O'Brien 1996, Katzenstein 1996, Marschner 1998, Hammer 1997, Cameron 1998, Ledergerber 1999
  91. "HPA Communicable Disease Surveillance Centre (HIV and STI Department) and the Scottish Centre for Infection and Environmental Health: Unpublished Quarterly Surveillance Tables"
  92. See AVERT's statistics section
  93. "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
  94. "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
  95. "Combination antiretroviral therapy and recent declines in AIDS incidence and mortality", Vittinghoff et al, J Infect Dis 179(3), 1999 March
  96. "AIDS Treatment Improves Survival: Answering the 'AIDS Denialists'", Mirken, AIDS Treatment News, September 2000
  97. "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
  98. "Epidemiology of human immunodeficiency virus-associated opportunistic infections in the United States in the era of highly active antiretroviral therapy", Kaplan et al, Clin Infect Dis 30 Suppl 1, April 2000
  99. For example: Connor 1994, Cooper 1996, Fiscus 1996, Shaffer 1999, Fiscus 2002, Harris 2002, Cooper 2002, Moodley 2003
  100. Centers for Disease Control and Prevention. HIV/AIDS Surveillance Report 2003, (Vol. 15).
  101. "Millions of Life-Years Saved with Potent Antiretroviral Drugs in the United States: A Celebration, with Challenges", Vermund, Journal of Infectious Diseases 194(1), 1 July 2006
  102. "Initial Theories", NIH, 1995
  103. "Epidemiologic Notes and Reports Immunodeficiency among Female Sexual Partners of Males with Acquired Immune Deficiency Syndrome (AIDS) -- New York", MMWR 31(52), January 1983
  104. "The Relationship Between the Human Immunodeficiency Virus and the Acquired Immunodeficiency Syndrome", NIH, 1995
  105. "The Duesberg Phenomenon", Cohen, Science 266, December 1994
  106. "Could Drugs, Rather Than a Virus, Be the Cause of AIDS?", Cohen, Science 266, December 1994
  107. "The AIDS Heresies", Harris, 1995
  108. "AIDS and Injection Drug Users", NIH, 1995
  109. "AZT and AIDS", NIH, 1995
  110. "Could Drugs, Rather Than a Virus, Be the Cause of AIDS?", Cohen, Science 266, December 1994
  111. For example: Palella 1998, Mocroft 1998, Mocroft 2000, Detels 1998, de Martino 2000, CASCADE 2000, Hogg 1999, Schwarz 2000, McNaghten 2000
  112. "AIDS Treatment Improves Survival: Answering the 'AIDS Denialists'", Mirken, AIDS Treatment News, September 2000
  113. "Answering the AIDS Denialists: Is AIDS Real?", Mirken, AIDS Treatment News, December 2000
  114. "Treating Opportunistic Infections Among HIV-Infected Adults and Adolescents", CDC, December 2004
  115. For more about AIDS definitions see WHO "Overview of Internationally Used HIV/AIDS Case Definitions"
  116. See AVERT's first history page
  117. UNAIDS/WHO (2004) 'Report on the global AIDS epidemic'
  118. UNAIDS (2010) 'UNAIDS report on the global AIDS epidemic'
  119. "Impact of the HIV epidemic on mortality in sub-Saharan Africa: evidence from national surveys and censuses", Timaeus, AIDS 12(suppl 1), 1998
  120. "The impact of AIDS on adult mortality: evidence from national and regional statistics", Blacker, AIDS 18(suppl 2), June 2004
  121. "The Impact of AIDS", United Nations, 2004
  122. "The World Health Report 2004", WHO, 2004
  123. "The impact of AIDS on adult mortality: evidence from national and regional statistics", Blacker, AIDS 18(suppl 2), June 2004
  124. "The Impact of AIDS", United Nations, 2004
  125. "Children on the Brink 2004", UNAIDS, 2004
  126. For example: Monasch 2004, Grassly 2005, Watts 2005, Makumbi 2005
  127. For example: Bayley 1991, Wabinga 1993, Wabinga 2000, Chokunonga 1999, Athale 1995, Sitas 2001
  128. For example: Harries 1997, Floyd 1999, Cantwell 1997, Glynn 2004
  129. "Global Tuberculosis Control: Surveillance, Planning, Financing, WHO Report 2004", World Health Organization
  130. "The Impact of AIDS", United Nations, 2004
  131. "The World Health Report 2004", WHO, 2004
  132. Data derived from UNAIDS/WHO Epidemiological Fact Sheets, 2004 edition, and UN population estimates for the year 2000
  133. Data derived from UNAIDS/WHO Epidemiological Fact Sheets, 2004 edition, and UN population estimates for the year 2000
  134. "Mortality and causes of death in South Africa, 2003 and 2004", Statistics South Africa, May 2006
  135. "Identifying deaths from AIDS in South Africa", Groenewald et al, AIDS 19(2), January 2005