- NEW YORK -- The origin of
AIDS is a mystery that twists through the forests of Africa and into the
bowels of a supercomputer in New Mexico. It pits hypotheses, scientists
and one persistent journalist against one another, rarely producing answers
that satisfy all the detectives on its trail.
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- While it is well understood what happens to the human
immunodeficiency virus -- the virus that causes AIDS -- once it is inside
the human body, it remains unknown how HIV got into humans to become one
of the world's worst plagues. Depending on whom you ask, the answer lies
with monkey hunters in Africa or a polio vaccine given to people in the
Congo in the 1950s.
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- The latter hypothesis is the subject of a documentary
that premiered in the United States last week at the Tribeca Film Festival
in New York City. The Origins of AIDS, directed by Peter Chappell and Catherine
Peix, follows the evidence laid out by British journalist Edward Hooper
in his 1999 book, The River. In it, Hooper proposed (based on nearly two
decades of research) that one man's part in the race to create the polio
vaccine launched the AIDS epidemic.
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- Hooper's conclusion, described by one biologist in the
film as "medical science's worst-hated hypothesis" directly challenges
the findings of other investigators who were interviewed for the documentary,
but whose diverging opinions ended up on the cutting-room floor.
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- "The public doesn't hear my view, nor does it hear
the view of anybody else who has doubts about this theory," said Beatrice
Hahn, a professor of medicine at the University of Alabama at Birmingham.
Hahn's work tracking chimpanzees in the forests of Africa has produced
a conclusion that nearly everyone agrees upon: HIV originally came from
chimpanzees.
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- But how and when the virus that infects chimpanzees --
simian immunodeficiency virus, or SIV -- became HIV is where Hooper and
his detractors diverge.
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- Several scientists, Hahn included, pinpoint bushmeat
hunting, an African practice during which hunters can incur bites or cuts
while hunting or preparing wild animals (including chimpanzees) for food.
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- "From all the things we know, it's pretty clear
that it crossed the species barrier naturally," said Dr. Michael Worobey,
assistant professor of ecology and evolutionary biology at the University
of Arizona, who has worked with Hahn to track the simian beginnings of
HIV.
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- Hooper's theory, which forms the plot line of the documentary,
argues against the bushmeat hypothesis. If bushmeat hunting was a historical
practice, Hooper wondered, why did the AIDS epidemic only take off in the
latter half of the 20th century? He found his answer in one of science's
most noble endeavors: polio eradication.
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- The film profiles Dr. Hilary Koprowski, an American scientist
racing Dr. Albert Sabin and Dr. Jonas Salk to create the polio vaccine,
primarily in the 1950s. Koprowski tested his oral vaccine in the Belgian
Congo. By mapping locations where the vaccinations were given and early
cases of AIDS emerged, Hooper showed a geographic correlation between the
two. The first documented case of HIV is from a blood sample taken in the
Congo in 1959.
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- "The location coincides dramatically," wrote
Hooper on his website. "The earliest known cases of AIDS occurred
in central Africa, in the same regions where Koprowski's polio vaccine
was given to over a million people in 1957-1960."
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- So, how could a vaccine give a monkey virus to humans?
In the documentary, grainy archival footage of white-coated lab scientists
shows the polio virus being grown in a soup of chopped-up monkey organs
before it is made into a vaccine.
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- Hooper charges that during Koprowski's vaccination campaign,
kidneys from chimpanzees infected with SIV were used to grow the virus.
The film cites a historical precedent: Another anti-polio campaign in the
1950s injected millions of people with vaccines containing the monkey virus
SV40, though none became ill from the injections.
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- [Note - According to many researchers and scientists,
SV40-contaminated Salk polio vaccines have led to the cancer deaths (kidney
and brain) of tens of millions of Americans. The statement above: 'though
none became ill from the injections' is total disinformation. Furthermore,
the evidence that HIV was created by the US DoD bioweapons program and
its various research contractors is compelling and well-documented. See
the works of Dr. Lorraine Day, MD, Dr. Robert Strecker, MD, Dr. Alan Cantwell,
MD, and Dr. Len Horowitz among others. All of these issues were covered
in my own book, AIDS Exposed, published in 1990. - ed]
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- Koprowski and scientists who worked with him deny that
chimp kidneys were used. Independent testing of leftover samples of the
vaccine in the United States, where it was produced using organs from other
types of monkeys, showed no traces of chimp DNA or SIV. However, the documentary
crew found several local workers in the Congo who allege that chimpanzee
kidneys were harvested and may have been used to produce more vaccine locally.
Samples actually used in the Congo are no longer available for testing.
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- But even if Hooper proves this allegation conclusively,
his detractors say he must still show that SIV transferred to humans at
the right time, from the right monkeys, carrying the right virus.
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- Bette Korber, a staff scientist at the Los Alamos National
Laboratory in New Mexico, has "collaborated" with a supercomputer
named Nirvana to chart the genetic history of HIV. Looking at the mutations
the virus experienced from the mid-1980s to 1999, Korber created a molecular
clock to determine the rate at which HIV changes.
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- Using that rate and calculating backward, she and Nirvana
dated the last common ancestor of HIV, the virus from which all present
variations descended, to 1931. If Korber is right, the virus must have
jumped from monkeys to humans before that date and well before Koprowski
was trying out his vaccine. Korber published her results in the journal
Nature in 2000.
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- While Korber and her computer contributed a time line
to the debate, Hahn has traipsed through the jungles of Africa picking
up chimp feces and urine. Analyzing those samples for genetic traces of
SIV, she has found that different subspecies of chimpanzees harbor different
variants of SIV, and only one of those variants is the likely ancestor
of HIV-1, the virus responsible for infecting more than 60 million people
worldwide.
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- "In 1999 we published a paper in Nature that said
that not all chimpanzee viruses are the likely source of HIV-1, only those
found in West Central Africa are," said Hahn. Hahn's findings place
the probable origin of the epidemic west of Koprowski's vaccination campaign.
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- More recently, Hahn and Worobey published findings from
a trip last year to the Democratic Republic of the Congo in the April 22,
2004, issue of Nature. The team went to the region where Koprowski's vaccine
campaign was carried out and collected 97 fecal and urine samples. One
contained genetic traces of SIV, but it was not the right kind. "It
was on the wrong branch of the phylogenetic tree," said Worobey. "So
instead of being a sister virus to HIV-1, it was a distant cousin."
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- Some investigators agree with Hooper.
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- "What Hooper got right was the timing," said
Preston Marx, chairman of the microbiology and immunology division at the
Tulane National Primate Research Center. "It looks like it mostly
happened after World War II and into the early '60s." Since the bushmeat
trade was in place well before that, Marx thinks human intervention must
have created the rapid spread in the second half of the century.
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- Still, Marx doesn't believe that chimpanzee kidneys were
used to make Koprowski's vaccine, and, even if they were, he is unsure
that the virus, which normally requires blood-to-blood or blood-to-mucosal
transmission, could be passed through organs used in a vaccine.
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- Hahn and Worobey are both disturbed that although filmmakers
Peix and Chappell interviewed them extensively and accompanied them on
research trips, the film only features scientists sympathetic to Hooper.
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- "We were not doing a scientific debate," said
the film's producer, Christine LeGoff, who wanted to tell Hooper's story
because she thinks his idea has not been given a fair shake. LeGoff said
she hopes to show the documentary in July at the XV International AIDS
Conference in Bangkok, Thailand.
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- And so the debate rages on, but, according to Hahn, not
for long. "We're going to do a comprehensive survey of chimpanzees
across sub-Saharan Africa. Five years from now this will all be moot."
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