From the 11 September 2000 ABC NEWS report of the testing of poliovaccine samples, Emma Ross of AP states:
"The tests were also designed to find traces of SIV, but found none. But that may not be important, Basilico said, because the virus could have died out after 40 years in a freezer."
From the 11 September 2000 Reuters report of the testing of poliovaccine samples, Patricia Reaney states:
"Although the original vaccine was used up during the programme, recent tests at three laboratories on 1950s-era polio vaccine samples found no evidence of HIV or a monkey virus or any DNA indicating that chimpanzee cells were used to prepare the vaccine."
From the 12 September 2000 New York Times report of the testing of poliovaccine samples, Lawrence Altman states:
"The tests do not conclusively disprove that possibility, however, because other vaccines for which samples were not kept could have been made from chimpanzee cells. The tests leave the mystery of the origins of AIDS unsolved."
"Even if the scientists had found evidence of a chimpanzee virus in the samples tested, that would not have proved that the virus started the epidemic. One theory is that simian viruses passed to humans in blood-to-blood contact like a cut during the killing of chimpanzees. But if so, it is not known why widespread transmission apparently did not begin until the 1950's."
ABCNEWS, Monday, September 11, 2000
By Emma Ross
The Associated Press
L O N D O N, Sept. 11 - Independent laboratory tests have found no evidence to support the theory that an early version of the polio vaccine tested in the 1950s inadvertently triggered the AIDS epidemic, scientists announced today.
The findings, presented at a conference at the Royal Society in London, are a blow to those who contend that HIV, the virus that causes AIDS, could have jumped species if medical researchers used chimpanzee kidneys to make some batches of the vaccine, which was given to about one million Africans between 1957 and 1961.
Scientists believe that HIV most probably originates from the type of SIV, or simian immunodeficiency virus, found in chimpanzees in western central Africa. But they don't know exactly how and when the chimp virus was transmitted to humans.
Samples of four different supplies of the vaccine, including some used in the African immunization program, were tested for traces of genetic material from animals. The laboratories were asked to identify which species the material came from.
No Chimp DNA
The prevailing theory of how HIV crossed to humans is that a hunter became infected around 1931 after being scratched by a chimp when trying to capture it or after cutting himself while butchering the animal.
Two laboratories in two different countries found that the vaccine samples they were given to test were made using monkey tissue. They found no chimp DNA, said Claudio Basilico, chairman of the microbiology department at New York University School of Medicine. Basilico chaired a committee set up by the vaccine's maker, the Wistar Institute in Philadelphia, Pa., to investigate claims that chimp tissue might have been used.
"Does this definitively rule out the vaccine theory? No, but it makes it more unlikely," Basilico said, noting that record keeping was sketchy at the time and that there may have been other samples not tested that were used in Africa.
The findings from the Max-Planck Institute in Leipzig, Germany, and the Pasteur Institute in Paris, did not dampen the views of writer Edward Hooper, chief proponent of the polio vaccine theory.
Hooper argues in a 1999 book, The River, that the Wistar Institute scientists might have used chimp kidneys to make some batches of the vaccine, and thereby could have inadvertently infected those receiving the vaccine with the chimp virus.
"This means nothing at all for the polio vaccine theory because different batches were prepared," Hooper said.
Other, untested or missing, batches might have yielded different results, he added.
Two of the scientists who conducted the African vaccine trials while working at the Wistar Institute vehemently denied any chimpanzee tissue was used to make the vaccine, branding Hooper's theory a "fantasy."
"We never used chimp kidneys," said Dr. Hilary Koprowski, former director of the Wistar Institute, who developed the vaccine. "I was there in 1957 and the author [Hooper] was not."
"I was working in the Wistar laboratory from 1957 to 1961 and I never saw or heard of chimpanzee cells" being used, added Dr. Stanley Plotkin, now a professor at the University of Pennsylvania.
Claims and Counter Claims
Hooper quoted testimonials from people involved in the research, such as lab technicians, hygienists and vets, that appeared to support his theory.
He quoted a lab technician, identified simply as Juma, as saying that kidneys were removed from chimps at the vaccine research station in Africa and sent to labs in Belgium and Rwanda.
Other witness accounts contended that chimp kidneys were sent to the Wistar Institute, and that some of the vaccine was made in a laboratory in Stanleyville, in what was then the Belgian Congo, now the Democratic Republic of Congo, he said.
Plotkin countered Hooper's claims with witness testimonials of his own.
Some of those statements came from the same people, but this time the testimony was contradictory. While Hooper quoted them as confirming the chimp theory, Plotkin quoted them as denying chimps were used.
Plotkin also showed slides listing workers from all three labs Hooper alleged had received the chimp kidneys. Beside nearly all of the names the same statement was printed: "never saw/heard of chimp cells."
He then displayed a list of scientific papers published on the research between 1957 and 1965 that each mention the use of monkey cells, but not chimps.
The tests were also designed to find traces of SIV, but found none. But that may not be important, Basilico said, because the virus could have died out after 40 years in a freezer.
By Patricia Reaney
LONDON, Sept 11 (Reuters) - AIDS experts on Monday dismissed a theory about the origins of the HIV virus which suggests the disease was spread to humans through a contaminated polio vaccine used in Africa in the late 1950s.
At a two-day conference on the origins of AIDS, they presented evidence rejecting claims by journalist Edward Hooper in the book "The River" that scientists inadvertently triggered the AIDS epidemic.
Hooper said a polio vaccine, developed by Professor Hilary Koprowski of Thomas Jefferson University in Philadelphia and tested in Europe and the Belgian Congo, used cultures of chimpanzee kidney cells that could have been infected with a monkey virus and transmitted to humans.
Koprowski and Dr Stanley Plotkin, of the University of Pennsylvania who worked with him in Africa 40 years ago, denied that chimpanzee kidneys were used and presented evidence from other scientists who supported them.
"The oral polio vaccine that has saved millions of lives has nothing to do with the dissemination of AIDS," Koprowski told conference.
Plotkin said the spread of HIV started in the 1930s, long before the vaccination programme in the Congo began, and the first cases of the disease are not associated with the vaccination.
"Mr Hooper made significant mistakes in reporting where vaccination was done, and in general, the epidemiology of AIDS is consistent with sexual transmission but does not agree with the polio hypothesis," he told a news conference.
Human immuno-deficiency virus (HIV) attacks a person's immune system and leads to full-blown AIDS, or acquired immune deficiency syndrome.
NOTHING IN LABORATORY TESTS TO SUPPORT THEORY
Although the original vaccine was used up during the programme, recent tests at three laboratories on 1950s-era polio vaccine samples found no evidence of HIV or a monkey virus or any DNA indicating that chimpanzee cells were used to prepare the vaccine.
"All the samples were found to be negative for HIV," Dr. Claudio Basilico, of New York University School of Medicine in New York and the Wistar Institute in Philadelphia, explained.
"There is nothing in the results from these tests to support the theory that HIV entered the human population during the late 1950s polio virus clinical trials in Africa," he added.
Dr Bette Korber, of the Los Alamos National Laboratory in New Mexico, said a genetic analysis of the HIV virus showed that the last common ancestor of the virus existed around 1931.
Her research showed the disease spread slowly and then increased in recent years, which is inconsistent with the polio theory.
"The beginning of diversification of these viruses was in the first half of the last century," she added.
Beatrice Hahn, of the University of Alabama in the United States, told the conference that all the genetic evidence points to HIV descending from a simian immunodeficiency virus (SIV).
She supports the generally accepted view that the virus jumped species when man was bitten by a monkey or by eating contaminated monkey flesh.
But despite the evidence against the polio vaccine theory, Hooper, a journalist, stood by his claims that the virus jumped to humans in the polio vaccine and that chimpanzee kidneys were used to make it.
"We should not be so ready to believe that our scientists know all the answers," he said.
He also dismissed suggestions that his book was hampering the worldwide fight to eradicate polio by questioning the safety of the polio vaccine.
New York Times, Tuesday, September 12, 2000
By LAWRENCE K. ALTMAN
Tests have failed to support a theory that the worldwide AIDS epidemic was touched off because an experimental oral polio vaccine used in Africa more than 40 years ago was made from chimpanzee tissue, scientists reported yesterday in London.
The tests do not conclusively disprove that possibility, however, because other vaccines for which samples were not kept could have been made from chimpanzee cells. The tests leave the mystery of the origins of AIDS unsolved.
Last year, in his book "The River," a British journalist, Edward Hooper, advanced the provocative theory that such a vaccine might have been made with chimpanzee tissue contaminated with an ancestor of the virus that was to cause AIDS. The theory is based in part on the general scientific belief that H.I.V.-1 derives from a simian virus in chimpanzees. H.I.V.-1 has caused an overwhelming majority of the cases of AIDS and H.I.V. infection.
Mr. Hooper suggested that the contamination might have come from an experimental oral polio vaccine prepared at the Wistar Institute, a research center in Philadelphia. Scientific papers published at the time did not say what primate tissues were used to make the vaccine, Mr. Hooper wrote. The institute has denied that its scientists used chimpanzee cells to prepare the vaccine.
After the theory was raised in 1992 in an article in Rolling Stone, the institute appointed an independent committee led by Dr. Claudio Basilico, chairman of the microbiology department at New York University, to look into the history. The panel recommended testing the remaining vaccine stores. Wistar did not carry out the tests then, it has said, because of a lack of scientific interest. Mr. Hooper's thesis was not widely accepted, but it led to calls for tests.
In February, Wistar provided the tiny quantities of remaining polio vaccine to Dr. Vincent Racaniello at the College of Physicians and Surgeons of Columbia University. He divided and coded the samples before delivering them to researchers at three independent laboratories, Dr. Shirley Kwok at Roche Molecular Systems in Pleasanton, Calif.; Dr. Svante Paabo at the Max Planck Institute in Leipzig, Germany; and Dr. Simon Wain-Hobson at the Pasteur Institute in Paris.
Dr. Kwok tested the samples for the presence of H.I.V. and S.I.V., its simian cousin. Dr. Paabo tested for the presence and species origin of two types of DNA. One comes from the nucleus, the other from mitochondria, which generate energy in the cell and are specific to a given species. Dr. Wain-Hobson did both.
The labs also tested samples from the Centers for Disease Control and Prevention. The Federal agency in Atlanta prepared samples that included old vaccine that it had stored.
The tests identified DNA from just one species of primate - the Asian macaque monkey, not the chimpanzee - in the Wistar samples, Dr. Basilico told the meeting in London.
He said, "There is nothing in the results to support the theory that H.I.V. entered the human population" during the polio clinical trials.
Even if the scientists had found evidence of a chimpanzee virus in the samples tested, that would not have proved that the virus started the epidemic. One theory is that simian viruses passed to humans in blood-to-blood contact like a cut during the killing of chimpanzees. But if so, it is not known why widespread transmission apparently did not begin until the 1950's.