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OPV AIDS hypothesis
According to the oral polio vaccine (OPV) AIDS hypothesis, the AIDS pandemic originated from live polio vaccines prepared in chimpanzee tissue cultures which were administered to up to one million Africans between 1957 and 1960. The specific populations were the first in the world to experience HIV-1 infections and AIDS some five years later.
The proponents of the hypothesis include journalist Edward Hooper as well as scientists Louis Pascal, Omar Bagasra, and the late W.D. Hamilton. They claim that the experimental oral vaccine, CHAT-1, was contaminated with simian immunodeficiency virus (SIV), a group of viruses endemic to African primates and widely accepted as the origin of HIV.
The OPV AIDS hypothesis is contradicted by scientific evidence, is unsupported by authoritative and leading institutions including the Centers for Disease Control and Prevention and the National Institute of Allergy and Infectious Diseases. It is specifically rejected by the scientific journals Nature and Science, as well as the community of scientists who research the genetic history of the AIDS viruses.
Additional recommended knowledge
Background: Polio vaccines
Two vaccines are used throughout the world to combat polio. The first polio vaccine, developed by Jonas Salk, is an inactivated poliovirus vaccine (IPV), consisting of a mixture of three wild, virulent strains of poliovirus, grown in a type of monkey kidney tissue culture (Vero cell line), and made noninfectious by Formalin treatment. The second vaccine, an oral polio vaccine (OPV), is a live-attenuated vaccine, produced by the passage of the virus through non-human cells at a sub-physiological temperature. The passage of virus produces mutations within the viral genome, and hinders the virus's ability to infect nervous tissue.
Both vaccines have been used for decades to induce immunity to polio, and to stop the spread of the infection. However, OPV has several advantages; because the vaccine is introduced in the gastrointestinal tract, the primary site of poliovirus infection and replication, it closely mimics a natural infection. OPV also provides long lasting immunity, and stimulates the production of polio neutralizing antibodies in the pharynx and gut. Hence, OPV not only prevents paralytic poliomyelitis, but also, when given in sufficient doses, can abort a threatening epidemic. Other benefits of OPV include ease of administration, low cost and suitability for mass vaccination campaigns.
Oral polio vaccines were developed by several groups, one of which was lead by Albert Sabin. Another group, led by Hilary Koprowski, developed its own attenuated vaccine strains. In 1952 Koprowski developed the TN strain at the Wistar Institute in Philadelphia, later identified as type 2 poliovirus. A type 1 strain, called SM, was reported in 1954. A less virulent version of the SM strain, called “CHAT”, was reported by Koprowski in 1957. In 1958, the National Institutes of Health created a special committee on live polio vaccines. The various vaccines were carefully evaluated for their ability to induce immunity to polio while retaining a low incidence of neuropathogenicity in monkeys. Based on these results, the Koprowski strains were eliminated and the Sabin strains were chosen for worldwide distribution.
Between 1957 and 1960, however, Koprowski would continue to administer his vaccine around the world. In Africa, the vaccines were administered to roughly one million people in the Belgian territories, now the Democratic Republic of the Congo, Rwanda and Burundi. Koprowski and his group published a series of detailed reports on the vaccination of 76,000 children under the age of 5 (and European adults) in the area of Leopoldville (now Kinshasa) in Belgian Congo from 1958-1960; these reports begin with an overview, next a review of safety and efficacy, then a 21-month follow-up and final report. An epidemic of polio erupted in Leopoldville two months after the vaccination campaign began and continued at low levels for at least the next 19 months; many dozens of children who had been vaccinated developed paralytic polio. During this same period, Koprowski immunized 40,000 children in Germany and more than seven million in Poland with his attenuated strains.
In the 1950s, before dangers inherent to the process were well controlled, seed stocks of vaccines were occasionally transported to distant regions, then standard tissue culture protocols were used to amplify the virus at local production facilities, in order to produce actual doses. It has been reported that specific biologic products, chiefly kidney cells for cultures and blood serum for media, were sometimes harvested from local primates and used in the production process, if wild or captive populations of appropriate species were available. In South Africa, African green monkey tissue was used to amplify the Sabin vaccine. In French West Africa and Equatorial Africa, baboons were used to amplify a vaccine from the Pasteur Institute. In Poland, the CHAT vaccine was amplified using Asian macaques.
Developments of hypothesis
San Antonio physician Eva Lee Snead was the first person to propose the hypothesis that AIDS could have crossed to humans via an infected polio vaccine. However she also argued, incorrectly that SV-40 might be a precursor to HIV.
In May 1987 Louis Pascal heard a radio broadcast by Dr. Snead explaining her hypothesis. Based on information in medical journals published in the 1950s and 1960s, and the information about the the first cases of HIV infection, he concluded that Dr. Hilary Koprowski's CHAT Type 1 vaccine administered in Belgian Congo between 1957 and 1960 was a likely source.. Pascal's paper about the hypothesis was submitted to several journals, but rejected by all. In their reply Nature stated that: "while the theory cannot be ruled out, it does not seem readily to fit the epidemiology of AIDS".
In the same year Blaine Elswood, an AIDS treatment activist who had developed similar ideas, contacted the journalist Tom Curtis about a "bombshell story." Curtis investigated the story and published an article in Rolling Stone 1992.. After that Dr. Koprowski sued the Rolling Stone and Tom Curtis for defamation, the magazine published a clarification which praised Dr. Koprowski and absolved him from any blame for the introduction of AIDS to the human population: "we never wished to suggest that it has been scientifically proven that Koprowski is the father of AIDS." The clarification also reiterated that the OPV hypothesis was "one of several disputed and unproven theories". Rolling Stone had to pay $US 1 in damages whilst incurring around $US 500,000 in legal fees for its own defense, while the legal action cost Dr Koprowski around $US 300,000. A contemporaneous defamation suit that Dr. Koprowski brought against the Associated Press was settled several years later but the terms are undisclosed.
A few scientists, notably the biologist W.D. Hamilton thought the hypothesis required serious investigation, but they received little support from the scientific community. Hamilton wrote a letter to Science in 1994 supporting Pascal and Curtis, but it was rejected by the editors.
Journalist Edward Hooper, who had already begun to investigate the origin of AIDS when the OPV hypothesis was first put forward gradually became convinced of its truth. After nine years of investigations, he detailed the hypothesis and evidence in his 1999 book, The River. In 2004, the Origin of Aids, a TV documentary strongly supportive of the OPV hypothesis, appeared on television stations globally.
In 2003, Edward Hooper and colleagues claimed to uncover testimony supporting the OPV hypothesis. Jacques Kanyama, a virology technician at the lab responsible for testing the CHAT vaccine and performing the initial set of vaccinations, alleged that batches of CHAT had been produced on site by Paul Osterrieth. Philip Elebe, a microbiology technician, claimed that tissue cultures were being produced from Lindi chimpanzees. Osterrieth disputes these claims,  saying that no vaccine was prepared locally and that only the CHAT vaccine from America was used.
Scientific investigationThe oldest confirmed sample of human tissue that shows the presence of HIV-1 is an archival sample of plasma collected from an anonymous donor in the city of Leopoldville, Belgian Congo (now Kinshasa) in 1959. The reporting authors state,
"Multiple phylogenetic analyses not only authenticate this case as the oldest known HIV-1 infection, but also place its viral sequence near the ancestral node of subtypes B and D in the major group, indicating that these HIV-1 subtypes, and perhaps all major-group viruses, may have evolved from a single introduction into the African population not long before 1959."A large vaccination campaign using the CHAT oral polio vaccine occurred in Leopoldville in 1958-1960, as described above.
...it can be stated with almost complete certainty that the large polio vaccine trial... was not the origin of AIDS.
In 2001, three articles published in Nature examined various aspects of the OPV-AIDS hypothesis, as did an article published in Science. In every case, the studies' findings argued strongly against any link between the polio vaccine and AIDS. An accompanying editorial in Nature concluded:
The new data may not convince the hardened conspiracy theorist who thinks that contamination of OPV by chimpanzee virus was subsequently and deliberately covered up. But those of us who were formerly willing to give some credence to the OPV hypothesis will now consider that the matter has been laid to rest.
Ongoing claims by proponents of the OPV-AIDS hypothesis that Kisangani chimpanzees were, indirectly, the true source of HIV-1 were again addressed in a 2004 study published in Nature. Here, the authors found that while SIV was present in chimpazees in the area, the strain of SIV infecting these chimpanzees was phylogenetically distinct from all strains of HIV, providing direct evidence that these chimps were not the source of HIV in humans.
Current oral polio-vaccine campaign in Africa
It should be noted that the debate over the OPV-AIDS hypothesis is in the context of a longstanding effort of the WHO and UN to achieve poliomyelitis eradication worldwide through use of the oral polio vaccine of Albert Sabin, which is thought to be safe and effective by virtually all medical authorities. If this long-term public-health goal could be achieved, poliomyelitis would join smallpox to become the second infectious disease of humans to be eradicated everywhere, which should make subsequent polio vaccinations unnecessary.
By 2003, cases of poliomyelitis had been reduced to just a small number in isolated regions of West Africa, with sporadic cases elsewhere. However, the disease has since resurged in Nigeria and in several other nations of Africa, which epidemiologists trace to refusals by certain local populations to allow their children to be administered the Sabin oral vaccine.
The expressed concerns of local populations often relate to feared sterility the vaccine might induce in young women, which seems irrational to most -- and some public-health workers argue that debate over the OPV-AIDS hypothesis have fueled these sorts of fears among contemporary Africans. Since 2003, these fears have spread among some in the Muslim community, and now polio has also resurged in areas of Pakistan, India, and Bangladesh as well. Other scientists, such as the late W.D. Hamilton of Oxford University, have argued that failures to adequately address medical mistakes of the past will only lead to similar failures in the future.
|This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "OPV_AIDS_hypothesis". A list of authors is available in Wikipedia.|