Study Rebuts Author’s Theory on AIDS Origin
LONDON — New scientific evidence unveiled Monday appears to undermine a British journalist’s controversial theory that the AIDS virus was passed from chimpanzees to humans during testing of a polio vaccine in Africa in the 1950s.
Independent tests on samples of the experimental vaccine, warehoused in the United States for nearly half a century, found the DNA of monkeys rather than chimpanzees, lending support to the polio researchers’ claims that they never worked with chimp tissue.
Tests on the vaccine also were negative for signs of simian immunodeficiency virus, the chimpanzee strain of HIV, the AIDS virus.
“We found no evidence to support the hypothesis of the polio vaccine origin of AIDS,†said Claudio Basilico, professor of microbiology at New York University School of Medicine.
Basilico chaired a committee set up by the vaccine’s creator, the Wistar Institute in Philadelphia, 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,†he said.
The results, unveiled at a Royal Society conference on the origins of HIV and AIDS, cast doubt on the theory, laid out by former British Broadcasting Corp. reporter Edward Hooper in his book “The River: A Journey to the Source of HIV and AIDS,†that the AIDS virus was spread to human beings by researchers using contaminated chimpanzee cells to develop a polio vaccine at the height of a world polio epidemic.
The 1,100-page book, which took Hooper nine years to research and write, shook the scientific world when it was released last year.
Hooper dismissed the test results, saying that those samples may not have been the ones to spread the disease.
“This means nothing at all for the polio vaccine theory, for I have demonstrated that different batches of [the] vaccine were prepared in labs in the United States, in Belgium and, in all likelihood, in Africa itself,†Hooper said. “Furthermore, it was common practice for different batches to be prepared in the cells of different primates.â€
Instead, Hooper claimed to have uncovered what he called the “smoking guns†proving that the research team led by renowned biologist Dr. Hilary Koprowski had used chimpanzees. He said he has eyewitness testimony that kidneys were extracted from chimpanzees in the former Belgian colonies of Africa, where the polio research was conducted and the CHAT polio vaccine given to at least a million people between 1957 and 1961.
And Hooper said he had reliable firsthand evidence that some of the kidneys were sent to Koprowski in the United States, to labs in Belgium and to a vaccine-making laboratory in Africa.
An indignant Koprowski called Hooper’s theory a “fantasy†and reiterated that “we never used chimp kidneys.†His associate in those days, Dr. Stanley Plotkin, insisted: “There is no smoking gun. There is no gun. There is no bullet. There is no motive. There is only smoke from Mr. Hooper.â€
Tensions ran high throughout the first day of the two-day meeting, with scientists whose reputations are on the line dismissing Hooper as an unscientific journalist, and a defensive Hooper implying that a fear of blame for millions of AIDS-related deaths and of lawsuits prevented the scientists from admitting their unwitting mistake.
“The facts of the matter are that there is a smoke screen around this, and the smoke screen is being put up by the people who made the vaccine,†Hooper said.
Scientists such as Plotkin could barely disguise their fury over what they seemed to regard as a wasted year trying to knock down the theory developed by Hooper, whose book has received widespread publicity.
“It is somewhat difficult to disprove a theory based not on fact but on a number of interesting possibilities,†Basilico said.
Most scientists believe the transfer of AIDS from chimps to people came from exposure to chimpanzee blood, either through chimp scratches and bites during capture, or through the consumption of chimpanzee meat.
Hooper argues that that theory lacks scientific proof and that no one has as yet produced scientific evidence to contradict his theory.
But recent findings by geneticist Bette Korber of Los Alamos National Laboratory suggest that the AIDS virus passed to humans at least 20 years before the polio trials.
Koprowski accused Hooper of having “operated with preconceptions without much attention to contradictory data.†He complained that as a result of Hooper’s book, Roman Catholic authorities in Kenya were advising members not to allow their children to be immunized with polio vaccines the clerics believe are contaminated with HIV. The book “may threaten the eradication of this terrible disease,†the polio researcher said.
*
Times medical writer Thomas H. Maugh II in Los Angeles contributed to this report.
