Polio Vaccine -- AIDS Theory Refuted

Four new scientific studies -- three published in Nature and one in Science -- essentially refute the theory that the AIDS epidemic began when thousands of Belgian Congo residents were given contaminated oral polio vaccine (OPV) in the 1950s. The argument that experiments with the OPV set off the epidemic was first made in Rolling Stone by Tom Curtis in 1992, then expanded by Edward Hooper in his 1999 book The River.

"The day of reckoning has come," said Hilary Koprowski, 84, the physician and immunologist who developed the experimental vaccine while working at the Wistar Institute in Philadelphia. The vaccine consists of weakened polio virus grown in living tissue -- usually kidneys taken from non-human primates. While conducting trials of the vaccine known as CHAT in Central Africa from 1957 to 1960, Koprowski's team maintained a colony of chimpanzees. Hooper alleges that Koprowski unwittingly used chimpanzee kidneys contaminated with simian immunodeficiency virus (SIV), the immediate ancestor of HIV. But Koprowski's assertion -- substantiated by incomplete records -- is that he never used chimpanzees.

Last year several samples of CHAT vaccine were tested and found to contain no HIV. In three new studies, researchers found that all the non-human primate DNA in the vaccine came from macaques -- Asian monkeys that do not carry SIV.

The fourth study seems to have disproved another Hooper theory. The numerous viral lineages that appeared in humans more or less simultaneously around the world can only be explained, he said, if already-different strains of HIV entered human beings at the same time, as might have happened with contaminated vaccines. But University of Oxford biologist Edward C. Holmes and colleagues analyzed nearly 200 Congo HIV samples and found virus from all lineages and many sub-lineages. This suggests that all Congo AIDS viruses -- and thus all the world's -- evolved from a single common ancestor and that global lineages were founded when a few non-Congolese people became infected and carried the virus to other parts of the globe.

Back to other CDC news for April 26, 2001

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