Duesberg hypothesis

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The Duesberg hypothesis is the claim, initially put forward by Peter Duesberg, that various non-infectious factors including recreational and pharmaceutical drug use are the cause of AIDS, and that HIV (human immunodeficiency virus) is a harmless passenger virus. The majority of the scientific community consider that Duesberg's arguments are the result of cherry-picking of scientific data^[1] and selectively ignoring evidence in favour of HIV's role in AIDS.^[2] There is broad scientific consensus that HIV is the cause of AIDS.

Contents 1 Proponents of the Duesberg hypothesis 1.1 Role of legal and illegal drug use 1.2 Current AIDS definitions 1.3 AIDS in Africa 1.4 Latency period 1.5 Duesberg's offer to infect himself 1.6 Duesberg claims that retroviruses like HIV must be harmless to survive 2 Common views of Duesberg and his opponents 3 Scientific response to the Duesberg hypothesis 3.1 Rejection of the risk-AIDS hypothesis 3.2 Effectiveness of antiretroviral medication 3.3 AIDS definitions 3.4 AIDS in Africa 3.5 Opponents claim that nearly all HIV-positive people will develop AIDS 4 Quotations 5 See also 6 References 7 External links

[edit] Proponents of the Duesberg hypothesis

The most prominent defenders of this theory are molecular cell biologist Peter Duesberg, biochemist and vitamin proponent David Rasnick, and journalist Celia Farber.

[edit] Role of legal and illegal drug use

Duesberg believes that there is a statistical correlation between trends in recreational drug use and trends in AIDS cases.^[3] He points to a rapid increase of AIDS cases in the 1980s that corresponds to a supposed epidemic of recreational drug use in the United States and Europe during the same time frame. Although the 1960s are notorious for a culture of drug use, Duesberg claims that drug usage (e.g. of heroin, cocaine, amphetamines, and poppers) has increased since then (with a temporary decline in the 1990s) and is still much higher than in the 1960s. According to the majority of experts, this claim is not supported by epidemiologic data.^[4]

Duesberg supposes that a major component of the present-day 'drug craze' is the use of 'poppers' (aka amyl nitrite and butyl nitrite), inhaled by mostly gay men to enhance their sexual experiences. The increased rate of the once rare Pneumocystis carinii pneumonia (PCP) and Kaposi's sarcoma are theorized to occur in patients that regularly use such inhalants. However, no evidence has been proposed for this theory.

Moreover, Duesberg asserts that treating AIDS with drugs such as the antiviral AZT, which became widely available about ten years after the beginning of the AIDS epidemic, has proven to be more dangerous than the recreational use of drugs such as heroin and cocaine. Some followers of Duesberg have claimed that AZT induces miscarriages and generates birth defects in children born to AZT-treated mothers, though this claim is not supported by clinical studies.^[5] AZT is still a common component of treatment for HIV/AIDS, but today it is almost always combined with other antiretroviral drugs such as protease inhibitors.

Duesberg explains the prevalence of AIDS among male homosexuals in Western countries such as the United States by pointing to the supposed prevalence of recreational drug use in this group. As reported in the medical literature, some male homosexuals in such countries use a great deal of sexual stimulants, including poppers, amphetamines, ethyl chloride, cocaine, and heroin.^{[citation needed]} Many of these drugs are known to inhibit the functioning of the body's immune system, at least briefly.^{[citation needed]} At the time of Duesberg's book, no one had done long-term studies on the effects of the chemicals on the immune system.

Several studies have examined the role of recreational drug use, sexual promiscuity, and others of Duesberg's supposed causes of AIDS. These studies have consistently found that, regardless of rates of drug use, sexual contacts, or other factors, infection with HIV was the only factor that predicted a decline in CD4 count and the development of AIDS.^[6][7] Such evidence has contributed to the scientific consensus that HIV is the cause of AIDS.

[edit] Current AIDS definitions

Although the first definitions of AIDS, prior to the discovery of HIV, mentioned no cause, the current diagnostic criteria for AIDS include the presence of HIV. Duesberg argues that a significant number of AIDS victims have died without proof of HIV infection.^[8] Since AIDS is now defined as X diseases plus HIV, victims with X diseases and no HIV don't count as AIDS patients. With such logic, claims Duesberg, it is impossible by definition to offer evidence that AIDS doesn't require HIV.

[edit] AIDS in Africa

Reported AIDS cases in Africa and other parts of the developing world, where only limited attempts are made to test for HIV infection, include people who do not belong to Duesberg's preferred risk groups of drug addicts and male homosexuals^{[citation needed]}, and it would be difficult to separate the collected data to exclude non-drug users and non-gays. Presence of the HIV virus is not required to designate a person as having HIV, in African populations.^{[citation needed]} In fact, Duesberg writes on his website that "There are no risk groups in Africa, like drug addicts and homosexuals."

According to Duesberg, the majority of African AIDS cases may be explained as malnutrition, parasitic infection, and poor sanitation, even though African AIDS cases have increased in the last two decades as HIV's prevalence has increased and as malnutrition and poor sanitation have declined in Africa.

The diseases developed by people with AIDS differ radically between African and Western populations. For example, tuberculosis is much more commonly diagnosed among AIDS patients in Africa than in Western countries, while PCP conforms to the opposite pattern.^[9] The aggressive, AIDS-associated form of Kaposi's sarcoma is fairly common among heterosexuals in some parts of Africa, but is largely restricted to gay men in the USA and Europe.^[10]

[edit] Latency period

There are many people who have HIV and have not yet developed AIDS and don't use the chemicals Duesberg hypothesizes cause AIDS. Mainstream scientists expect that nearly all of these people will develop AIDS within ten to fifteen years after infection, but in the meantime, they are relatively healthy. According to the Duesberg hypothesis, these people will remain as healthy as anyone else.

[edit] Duesberg's offer to infect himself

Duesberg's most radical challenge to the HIV-AIDS hypothesis is his offer to infect himself with HIV. However, he claims that it is not permissible for him to do so without the approval of the U.S. National Institutes of Health and the university that employs him. Critics regard this as a stunt, because the NIH cannot ethically give "approval" for a person to knowingly infect themselves with HIV.

[edit] Duesberg claims that retroviruses like HIV must be harmless to survive

Peter Duesberg argues that retroviruses like HIV must be harmless to survive, because after reverse transcription of their RNA to DNA, they depend on cell division to replicate. They cannot replicate in neurons, for example, because these cells do not divide (after the age of one year).^{[citation needed]} The normal mode of proliferation of retroviruses is from mother to child, thus implying the survival of the infected mother and the child for decades.^{[citation needed]} Humans carry more than 300 different harmless retroviruses in their DNA.^{[citation needed]} For example the gene encoding for amylase production in saliva is due to retroviral DNA inserted just upstream of the body's amylase gene.^{[citation needed]} The retroviral DNA's promoter sequence induces the gene to be transcribed in the mouth.^{[citation needed]}

Most researchers believe that some retroviruses can cause cancer. Peter Duesberg rejects this idea.

[edit] Common views of Duesberg and his opponents

Nitrite inhalants ("poppers") are dangerous drugs -- independently of the HIV-AIDS discussion. Nitrites can cause methemoglobinemia and have been observed to be mutagenic, carcinogenic and immunosuppressive in animals and humans.^{[citation needed]} They have an effect on both humoral and cellular immunity.^{[citation needed]} Nitrite inhalants have also been found to stimulate viral replication and secretion of viral proteins involved in Kaposi's sarcoma growth.^{[citation needed]}

Thus, both sides agree that nitrite inhalants (and other drugs) at least accelerate the development of Kaposi's sarcoma and other AIDS-defining diseases,^{[citation needed]} i.e. that nitrites are a cofactor — but they don't agree on nitrites or other drugs being the main cause of AIDS or Kaposi's sarcoma.

[edit] Scientific response to the Duesberg hypothesis

The current consensus in the scientific community is that the Duesberg hypothesis has been refuted by the huge mass of available evidence, showing that causation of AIDS by HIV is clear, that virus numbers in the blood correlate with disease progression, and that a plausible mechanism for HIV's action has been proposed.

In the December 9, 1994 issue of Science (Vol. 266, No. 5191),^[2] Duesberg's methods and claims were evaluated. The authors concluded that:

• it is abundantly evident that HIV causes disease and death in hemophiliacs.^{[11] [12]}
• HIV fulfills Koch's postulates, which are one set of criteria for demonstrating a causal relationship between a microbe and a disease.^[13]
• the AIDS epidemic in Thailand cited by Duesberg as confirmation of his hypothesis is in fact evidence of the role of HIV in AIDS.^[14]
• AZT and illicit drug use, contrary to Duesberg's claims, do not cause an immune deficiency similar to that seen in AIDS.^[15]

[edit] Rejection of the risk-AIDS hypothesis

Several studies have specifically addressed Duesberg's claim that recreational drug abuse or sexual promiscuity were responsible for the manifestations of AIDS. Schechter et al prospectively studied a group of 715 homosexual men in the Vancouver area. Approximately half of these men were HIV-seropositive or became so during the follow-up period, and the remainder were HIV-seronegative. After more than 8 years of follow-up, despite drug use, sexual contact, and other supposed risk factors in both groups, AIDS developed only in those patients who were HIV-seropositive. Similarly, CD4 counts dropped in the patients who were HIV-infected, but remained stable in the HIV-negative patients, in spite of similar rates of risk behavior.^[6] The authors concluded that "the risk-AIDS hypothesis... is clearly rejected by our data," and that "...The evidence supports the hypothesis that HIV-1 has an integral role in the CD4 depletion and progressive immune dysfunction that characterise AIDS."^[6]

Similarly, the principal investigators of the Multicenter AIDS Cohort Study (MACS) and the Women's Interagency HIV Study (WIHS) — which between them observed more than 8,000 Americans — concluded that, "The presence of HIV infection is the only factor that is strongly and consistently associated with the conditions that define AIDS."^[7]

[edit] Effectiveness of antiretroviral medication

The vast majority of people with AIDS have never received antiretroviral drugs, including those in developed countries prior to the licensure of AZT in 1987, and people in developing countries today where very few individuals have access to these medications.^[16]

As with medications for any serious diseases, antiretroviral drugs can have toxic side effects. However, there is no evidence that antiretroviral drugs cause the severe immunosuppression that typifies AIDS. Abundant evidence exists that antiretroviral therapy, when used according to established guidelines, can improve the length and quality of life of HIV-infected individuals.

In the mid-1980s, clinical trials enrolling patients with AIDS found that AZT given as single-drug therapy conferred a modest (and short-lived) survival advantage compared to placebo. Among HIV-infected patients who had not yet developed AIDS, placebo-controlled trials found that AZT given as single-drug therapy delayed, for a year or two, the onset of AIDS-related illnesses. Significantly, long-term follow-up of these trials did not show a prolonged benefit of AZT, but also did not indicate that the drug increased disease progression or mortality. The lack of excess AIDS cases and death in the AZT arms of these placebo-controlled trials effectively counters the argument that AZT causes AIDS.^[17]

Subsequent clinical trials found that patients receiving two-drug combinations had up to 50 percent improvements in time to progression to AIDS and in survival when compared to people receiving single-drug therapy. In more recent years, three-drug combination therapies have produced another 50 to 80 percent improvement in progression to AIDS and in survival when compared to two-drug regimens in clinical trials.^[18] Use of potent anti-HIV combination therapies has contributed to dramatic reductions in the incidence of AIDS and AIDS-related deaths in populations where these drugs are widely available, an effect which clearly would not be seen if antiretroviral drugs caused AIDS.^{[19][20][21][22][23][24][25][26][27][28]}

[edit] AIDS definitions

Early definitions of AIDS did not include any reference to the cause, as the cause of AIDS was initially unknown. The changes were made as the weight of evidence accumulated and consensus was developed.

For this aspect of the debate, a particularly relevant feature of AIDS is the relentless decline of immune system function. Without anti-HIV drug therapy, the collapse of the immune system is essentially unstoppable, although it may proceed in an uneven fashion. By contrast, a person who receives chemotherapy for cancer can expect to have severely depressed immune system function for a time after treatment ends, and then to recover to normal or near-normal stages. Assuming no further need for chemotherapy, this person may expect essentially normal immune function for the rest of his or her life.

AIDS patients, however, do not recover significantly from downturns in immune function; in the absence of HIV suppression, their immune system eventually collapses. The natural course of AIDS is the long-term and essentially irreversible loss of immune system function.^[29] Other than HIV infection, which Duesberg proponents reject, there are very few known causes of chronic immune system failure, notably most forms of leukemia and a few rare genetic disorders, and these cases are both uncommon and not in the Duesberg hypothesis' risk groups of intravenous drug users and male homosexuals.

Although proponents of the Duesberg hypothesis assert the existence of HIV-negative people with long-term immune system failure (other than due to known causes, like leukemia), they have yet to publish case studies on any such individuals or to work with any medical centers to have other known causes excluded.

Importantly, there is nothing about the datasets that forces researchers to pay attention to the HIV status of a participant; in fact, studies show intriguing differences in AIDS behaviors based on factors other than HIV infection. For example, hemophiliacs who acquired HIV through contaminated blood products were less likely to develop certain opportunistic infections (and more likely to die of liver failure) than people who acquired HIV through sexual contact.

[edit] AIDS in Africa

The Duesberg hypothesis argues that AIDS in Africa is the result of poor sanitation and malnutrition, not HIV. Critics note the following facts:

• AIDS in Africa has increased during the last two decades, in tandem with the prevalence of HIV.^{[citation needed]}
• Sanitation and nutrition, on the other hand, have noticeably improved since the 1980s, when the Ethiopian famine was prominent in the news, yet AIDS case rates continued to increase.^{[citation needed]}
• AIDS in Africa largely kills sexually active working-age adults.^{[citation needed]}
• The groups that have HIV are the ones dying from AIDS. For example, in areas where surveys show 50% of people with HIV are women, that area will show that 50% of people dying from AIDS are women. In areas where 20% of HIV+ people use recreational drugs, then 20% of the people dying from AIDS use recreational drugs.^{[citation needed]}

If the Duesberg hypothesis is right, one wonders why AIDS kills so many otherwise healthy adults in Africa at the same time that health has improved among the children and the elderly, who are normally the most vulnerable to poor sanitation and malnutrition, and least vulnerable to sexually transmitted diseases.

[edit] Opponents claim that nearly all HIV-positive people will develop AIDS

Duesberg claims as support for his idea that many drug-free HIV+ people have not yet developed AIDS; other scientists note that many other drug-free HIV+ people have developed AIDS, and that if they wait long enough, it is very likely that nearly all of the HIV+ people will develop AIDS. Mainstream scientists also note that drug-using HIV-negative people do not seem to suffer from immune system collapse.

[edit] Quotations

• Warren Winkelstein Jr., a Berkeley AIDS researcher, characterized Duesberg's continued publicizing of his theory as "irresponsible, with terribly serious consequences".^[2]

• Dr. Helene Gayle, a former director of the National Center for HIV, STD and TB Prevention at the Centers for Disease Control and Prevention and president of the International AIDS Society (IAS), has said that Duesberg's message has been "very damaging" to AIDS prevention projects.^[2]

• According to Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, "The vast majority, 99.99999 percent of the scientific community, is convinced that the data is overwhelming that it causes AIDS. When people like Duesberg come and say, 'You haven't proven this; you haven't proven that,' the fact is we have."^[30]

• Former IAS president Dr. Mark Wainberg has suggested that Duesberg is "probably the closest thing we have in this world to a scientific psychopath."^[31]

• Nature's editor John Maddox wrote in 1993 that, "Duesberg has forfeited the right to expect answers by his rhetorical technique. Questions left unanswered for more than about ten minutes he takes as further proof that HIV is not the cause of AIDS. Evidence that contradicts his alternative drug hypothesis is on the other hand brushed aside."^[32]

• Science's special news report, which followed a 3-month investigation, found that "Mainstream AIDS researchers argue that Duesberg's arguments are constructed by selective reading of the scientific literature, dismissing evidence that contradicts his theses, requiring impossibly definitive proof, and dismissing outright studies marked by inconsequential weaknesses."^[2]

[edit] See also

• AIDS reappraisal

[edit] References

[edit] External links

• Peter Duesberg's website
• AIDS ACQUIRED BY DRUG CONSUMPTION AND OTHER NONCONTAGIOUS RISK FACTORS - PETER H. DUESBERG
• The Evidence That HIV Causes AIDS: NIH fact sheet.
• How HIV Causes AIDS NIH fact sheet.