HUMAN IMMUNODEFICIENCY VIRUS
Appendix 2: DOES HIV CAUSE AIDS?
Dr Richard Hunt
Despite the overwhelming evidence that HIV is the causative agent of AIDS, there are still many things that we do not know about the virus. Some people say that all that is necessary for AIDS is an HIV infection. Others invoke co-factors. A small but influential minority say that HIV is an unjustly maligned by-stander that is found in many immunocompromised states but is not the cause of the disease. The most outspoken of these are Drs Peter Duesberg and Kary Mullis.
The following are the arguments raised by those who believe that HIV does not cause AIDS:
i) HIV is not in semen.
In fact, it is actually found to a high degree in most investigations.
ii) Viruses work exponentially to produce new virions and disease.
This statement confuses virus in a cell, where this is true in many cases, with disease in individual. There are numerous examples of slow progressive viral diseases.
iii) Viruses do not cause disease when neutralizing antibody is present.
This is not true. There are examples of diseases which progress in spite of the presence of antibody.
iv) Fewer than 1 in 10,000 T4 cells infected.
We now know that the presence of HIV can cause uninfected cells to undergo apoptosis
v) Few hemophiliacs get AIDS; instead, they die of immune suppression by therapeutic blood proteins.
HIV positive hemophiliacs get immune suppression but HIV negative ones do not.
vi) Transfusion of HIV contaminated blood not been shown to give AIDS.
In a Mexican study of 39 patients given HIV+ blood, AIDS occurred in 3% of the recipients within 12 months, 50% after 29 months, 75% after 36 months, 100% after 48 months. The mean survival time after AIDS onset was 9 months.
vii) HIV does not fulfill Koch's postulates.
Postulate 1: An infectious agent occurs in each case of a disease in sufficient amounts to cause pathology.
It is said that there are many cases of AIDS without HIV. It is to be expected that there would be other causes of immune suppression and so there would be AIDS-like diseases without HIV. Nevertheless, the overwhelming majority of AIDS-like immunosuppressive diseases occur in HIV-infected persons.
Postulate 2: A specific infectious agent is not found in other diseases.
This was later abandoned by Koch when it was found that one agent can cause more than one specific disease.
Postulate 3: After isolation and culture, the infectious agent can induce the disease in another individual. The infectious agent can then be isolated from the newly infected host.
In the case of HIV which only causes disease in humans, this is difficult to do as there is, naturally, a lack of volunteers. However, this postulate has been satisfied by the following evidence:
Cloned simian immunodeficiency virus (SIV) causes an AIDS-like disease within a year in macaques. Characteristics of the disease are low CD4+ T4 cell count and opportunistic infections such as pneumocystis pneumonia.
HIV2, which is closely related to HIV1 and cause AIDS in western Africa, can cause AIDS in some moneys such as baboons. Again specific CD4+ cell loss was observed.
The best evidence comes from a laboratory accident that occurred in the late 1980's. Three laboratory workers who worked with the virus became infected with purified cloned HIV1. After 5 to 7 years, all three had low CD4+ T4 cell counts and one had developed pneumocystis pneumonia and died. They were serologically positive for HIV. The HIV from all three patients was sequenced and found to be the same as the virus with which they appeared to be infected. One got the virus by a puncture wound when handling a centrifuge used for HIV concentration, one through mucous membrane and facial exposure and the other had direct contact with the virus though the actual route of infection was not known.
None of the three had lifestyles that would predict the possibility of AIDS. The report of the accident was published in 1993 and so the infections clearly occurred several years before that. The laboratory worker who developed pneumocystis pneumonia had not received AZT (which Duesberg has implicated as a possible cause of AIDS).
Thus, all three exposed patients had severe immunodeficiency (as a result of specific CD4 cell loss) after being infected with HIV. In 1994, Jon Cohen (Science vol 266, p 1647) asked Duesberg about his position on HIV as a result of the reports of the three lab workers. Duesberg did not agree that Koch's postulates had been satisfied. He pointed out that as of December 1994, 2 of the 3 lab workers did not have opportunistic infections but did not address the one person who did.
With regard to Koch's postulates, Duesberg has argued that the following criteria must be met to show that HIV causes AIDS
1. The microorganism must be found in all cases of the disease.
2. It must be isolated from the host and grown in pure culture.
3. It must reproduce the original disease when introduced into a susceptible host.
4. It must be found in the experimental host so infected.
It is now apparent that:
1. Virtually all AIDS patients are HIV-infected
2. HIV can be isolated from virtually all AIDS patients, as well as in almost all seropositive individuals with both early- and late-stage disease
3. Laboratory workers accidentally infected with concentrated purified HIV have developed AIDS
4. HIV has been isolated from these individuals
It should also be noted that:
HIV has always preceded AIDS in a population.
HIV is the single common factor between AIDS sufferers who are gay San Franciscans, African female heterosexuals, hemophiliacs, children, intravenous drug users.
Within any risk group only the HIV+ individuals get AIDS. It could be argued that all members of these groups are subject to immunosuppression but this is not the case with wives of hemophiliacs.
There is a better correlation between HIV and AIDS than between cigarettes and lung cancer.
Summary of the abundant evidence that HIV is the causative agent of AIDS:
1. Before the appearance of HIV, AIDS-like syndromes were rare, today they are common in HIV-infected people
2. AIDS and HIV are invariably linked in time, place and population group
3. The main risk factors for AIDS are sexual contact, transfusions, IV drugs, hemophilia. These have existed for years but only after the appearance of HIV, has AIDS been observed in these populations
4. Infection by HIV is the ONLY factor that predicts that a person will develop AIDS
5. Numerous serosurveys show that AIDS is common in populations with anti-HIV antibodies but is rare in populations with a low seroprevalence of anti-HIV antibodies
6. Cohort studies show that severe immunosuppression and AIDS-defining illnesses occur exclusively in individuals that are HIV-infected
7. Persistently low CD4+ T4 cell counts are extraordinarily rare in the absence of HIV or another known cause of immunosuppression
8. Nearly everyone with AIDS has anti-HIV antibodies
9. HIV can be detected in nearly everyone with AIDS
10. HIV does fulfill Koch's postulates
11. New-born infants with no behavioral risks develop AIDS if infected as a result of the mother being HIV-infected
12. An HIV-infected twin will develop AIDS, while the uninfected twin will not
13. Since the appearance of HIV, mortality has increased dramatically among hemophiliacs
14. Studies of transfusion-acquired AIDS has repeatedly led to discovery of HIV in recipient as well as donor
15. Sex partners of HIV-infected hemophiliacs and transfusion patients acquire the virus and AIDS without other risk factors
16. HIV infects and kills CD4+ T cells in vitro and in vivo
17. HIV damages CD4 precursor cells
18. Body viral (HIV) load correlates with progression to AIDS
19. HIV is similar in its genome and morphology to other lentiviruses that often cause immunodeficiency, slow wasting disorders, neurodegeneration and death
20. Baboons develop AIDS after inoculation with HIV2 that also causes AIDS in humans
21. Asian monkeys develop an AIDS-like disase after inoculation with simian immunodeficiency virus
Clearly, the correlations between HIV and AIDS are very striking indeed.