- Health officials say they've got Mad Cow under control,
but millions of unaware people may be infected. Why it could still turn
into an epidemic
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- NEWSWEEK March 12 issue -
Peter Stent was a seasoned dairyman' but he had never seen anything like
this. Just before Christmas, in 1984, one of his cows at Pitsham Farm in
South Downs, England, started shedding weight, losing its balance and acting
as skittish as a cat.
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- When the vet came to investigate, the animal was acting
completely crazy - drooling, arching its back, waving its head, threatening
its peers. And by the time it died six weeks later, Stent was seeing the
same symptoms in other cows. Nine were soon dead, and no one could explain
why. The vet dubbed the strange malady Pitsham Farm syndrome, since it
didn't seem to exist anywhere else. Little did he know.
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- Alison Williams was 20 years old at the time, and living
in the coastal village of Caernarfon' in north Wales. She was bright and
outgoing, a business student who loved to sail and swim in the nearby mountain
lakes. But her personality changed suddenly when she was 22. She lost interest
in other people, her father recalls, and quit school to live at home with
her parents and her brother. She still enjoyed the outdoors, but she took
to sitting alone on her bed, staring out the window for hours at a time.
By 1992, Alison was having what her doctors diagnosed as nervous breakdowns,
and by 1995 she had grown paranoid and incontinent. "A month before
she died, she went blind and lost use of her tongue, her dad recalls. "She
spent her last five days in a coma.
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- SOMETHING BIGGER?
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- Anyone with a television has heard such stories, maybe
even sussed out the connection between them. Mad-cow disease, or bovine
spongiform encephalopathy (BSE), has killed nearly 200,000 British and
European cattle since it cropped up on Pitsham Farm. The human variant
that Alison Williams contracted has claimed 94 lives as well. What few
of us realize is that these tolls could mark the beginning of something
vastly bigger. No one knows just how BSE first emerged. But once a few
cattle contracted it, 20th-century farming practices guaranteed that millions
more would follow. For 11 years following the Pitsham Farm episode, British
exporters shipped the remains of BSE-infected cows all over the world,
as cattle feed. The potentially tainted gruel reached more than 80 countries.
And millions of people"not only in Europe but throughout Russia and
Southeast Asia"have eaten cattle that were raised on it.
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- "We have no idea how many deaths we,re going to
see in the coming years. We,ve been checkmated. - DR. FREDERIC SALDMANN
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- It's possible, of course, that the worst is already behind
us. After dithering for a decade, governments in the United Kingdom and
Europe have lately taken bold steps to control BSE. The number of bovine
cases is now falling in Britain"and the United States has yet to even
report one. American officials banned British cattle feed in 1988, as soon
as scientists implicated it in BSE, and later barred the recycling of domestic
cows as well. The U.S. government, the cattle industry and many experts
now voice confidence in the nation's fire wall and say the risk to consumers
is slight. In truth, however, America's safeguards and surveillance efforts
are far weaker than most people realize. And in many of the developing
countries that now face the greatest risk, such efforts are nonexistent.
How many of the world's cattle are now silently incubating BSE? How many
people are contracting it? The truth is, we don't know. "We have no
idea how many deaths we,re going to see in the coming years, says Dr. Frederic
Saldmann' a French physician who has recently seen both cows and people
stricken in his country. "We,ve been checkmated.
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- Mad cow is the creepiest in a family of disorders that
can make Ebola look like chickenpox. Scientists are only beginning to understand
these afflictions. Known as transmissible spongiform encephalopathies,
or TSEs, they arise spontaneously in species as varied as sheep, cattle,
mink, deer and people. And once they take hold they can spread. Some TSEs
stick to a single species, while others ignore such boundaries. But each
of them is fatal and untreatable, and they all ravage the brain"usually
after long latency periods"causing symptoms that can range from dementia
to psychosis and paralysis. If the prevailing theory is right, they're
caused not by germs but by "prions"normal protein molecules that
become infectious when folded into abnormal shapes. Prions are invisible
to the immune system, yet tough enough to survive harsh solvents and extreme
temperatures. You can freeze them, boil them, soak them in formaldehyde
or carbolic acid or chloroform, and most will emerge no less deadly than
they were.
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- ILL-TEMPERED SHEEP
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- The prion story starts in the 1730s, when shepherds in
Britain and Europe described the disease we call scrapie. Like Peter Stent's
cows, afflicted sheep would grow ill-tempered and wobbly. Then' over three
to six months, they would suffer seizures, paralysis, blindness and death.
Scrapie is still common in sheep, but doesn't seem to strike people. As
far as we know, no one has ever gotten sick by eating infected mutton.
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- Dr. Carleton Gajdusek knew nothing of scrapie when he
landed in Papua New Guinea in the 1950s. But Gajdusek, an American pediatrician
and virologist employed by the National Institutes of Health in Maryland,
soon encountered something similar. A strange neurological disease was
killing the Fore people of the country's Eastern Highlands"especially
the women and children. The Fore called the condition "kuru, which
means shaking or shivering, and they knew its 16-month progression well:
tremors and an unsteady gait, followed by slurred speech, joyless laughter
and, finally' stupor and death.
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- The Fore knew kuru as a curse cast by sorcerers. Like
most outsiders, Gajdusek suspected it was an epidemic disease, somehow
related to the tribe's eating habits. Fore men supplemented their bean-and-sweet-potato
diets with small game, but women and children lacked protein. The women
had recently created a ritual to fill the gap. Instead of burying dead
loved ones, they ate them. As Richard Rhodes recounts in his 1997 book,
"Deadly Feasts, "They did not eat lepers or those who died of
diarrhea, but the flesh of women killed by [kuru] they considered clean.
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- KURU AND CANNIBALISM
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- The link between kuru and cannibalism seemed clear enough.
But as he examined living patients, Gajdusek saw no outward signs of infection"no
fever, no inflammation"and culture tests turned up nothing suspicious
in their spinal fluid. By sending autopsy samples to his colleagues back
in Maryland, Gajdusek did learn that the patients, brains resembled those
of people with Creutzfeldt-Jakob disease (CJD), a rare and fatal brain
condition that German researchers had discovered in the 1920s. Both conditions
filled the brain with "vacuoles, small cavities resembling the holes
in a sponge. And despite some differences, they ran essentially the same
course. But that only deepened the mystery. As far as anyone knew, CJD
was just a biochemical fluke, a disease that strikes randomly and infrequently
all over the world. Kuru was spreading like a plague.
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- Gajdusek published several reports on kuru over the next
couple of years, and one of them caught the attention of Dr. William Hadlow,
a scrapie expert. Hadlow noticed that the vacuoles in Gajdusek's kuru brains
resembled those he,d seen in sheep. The symptoms sounded familiar, as well.
In a letter to The Lancet, Hadlow listed the parallels between kuru and
scrapie, and posed a tantalizing question. Studies had shown that healthy
animals developed scrapie when injected with a sheep's diseased brain tissue.
What would happen' he wondered, if you injected a healthy animal with brain
tissue from a kuru victim? Would this disease spread in the same way?
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- Question: What is a prion? Answer: Abnormally folded
proteins called prions are involved in a variety of neurological diseases
in humans. Variations in the folding lead to different effects on the brain
and consequently to different symptoms."
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- Creutzfeldt-Jakob Disease (including the familial, sporadic,
and medically-transmitted forms)
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- * Pathology: Infected cells in the brain swell with water,
producing a spongey appearance when cross-sections of brain tissue are
examined under a microscope. These holes are called vacuoles. In addition'
some neurons die. Damage is concentrated in the gray matter of the cerebral
cortex.* Onset: After age 50 * Progression: The disease begins subtly with
forgetfulness, depression' personality changes, strange physical sensations
and problems with eyesight. It soon progresses to dementia, jerking muscles
and blindness before leading finally to death. The course of the disease
is mercifully quick, taking only 4 to 6 months from the onset of symptoms
to death.
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- Gerstmann-Straussler-Scheinker Syndrome
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- * Pathology: Insoluble masses of proteins (called plaques)
develop in the brain' but no spongiform vacuoles. Damage is concentrated
in the cerebellum, the part of the brain that controls motor function.
* Onset: After age 50 * Progression: In many ways, the disease is even
crueler than CJD. Because the cerebellum is impaired, symptoms start with
trembling and loss of coordination. Motor damage makes walking, speaking
and even swallowing difficult. Dementia develops very late in the process,
so patients are aware of what's happening to them. The disease progresses
slowly-taking on average 2 to 6 years from onset of symptoms to death,
but occasionally taking as long as 10 years.
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- Fatal Insomnia (including both the familial and sporadic
forms)
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- * Pathology: Prions accumulate in the thalamus, the brain's
communications center * Onset: Mean age of 48. Range, 25 to 61 * Progression:
Symptoms begin with increasing insomnia, in which patients may eventually
be able to sleep no more than one hour a night. Panic attacks and phobias
are common. Hallucinations follow. The last stage involves dementia, muteness,
total insomnia and sudden death. The disease generally takes around 18
months to progress from onset of symptoms to death.
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- Kuru and new variant Creutzfeldt-Jakob Disease
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- * Pathology: Prions accumExtensive spongiform vacuoles
and plaques develop throughout the gray matter and cerebellum.* Onset:Average
age 27. Range, 16 to 48 Mean age of 48. Range, 25 to 61 * Progression:
The first symptoms are anxiety and depression' followed by trembling, loss
of coordination' and finally dementia. The disease takes about 16 months
to progress from onset of symptoms to death.
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- To find out, Gajdusek and a colleague started injecting
chimps and monkeys with the ground brains of Fore tribeswomen. By 1965
they had shown that kuru was transmissible. Gajdusek then repeated the
experiment with brain tissue from an American CJD victim and got the same
result. These astonishing discoveries helped control kuru in New Guinea.
They also won Gajdusek a Nobel Prize. He had shown that scrapie, kuru and
CJD could all spread and kill in the same manner. Unfortunately' the responsible
pathogens were still unknown. And as it turned out, eating one's relatives
was not the only way to contract them.
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- GLAND HARVESTING
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- While Gajdusek and his colleagues were investigating
kuru, other scientists were pursuing the secrets of growth and maturation"and
making equally thrilling discoveries. Endocrinologists had found a rich
store of hormones in the pituitary' a pea-sized gland near the front of
the brain. And by the early 1960s they had shown that one of these substances"human
growth hormone"could help dwarves reach more normal heights. Human
cadavers were the only known source of hGH, and demand was intense. So
in 1963, the federal government created a National Pituitary Agency to
harvest and distribute the glands. Over the next two decades, roughly 8,200
kids got hGH through the agency' and similar programs cropped up throughout
Europe.<http://www.msnbc.com/news/NW-talk_Front.asp
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- All seemed well until 1984, when a troubling pattern
emerged. In its common "sporadic form, Creutzfeldt-Jakob disease is
rare in people under 50. Yet patients who,d received growth-hormone injections
were getting the disease in their 20s. By spring 1985 there were four such
cases on record, and the implication was obvious: the medical establishment
had created the high-tech equivalent of a Fore funerary feast. No one knew
how many pituitary donors had been silently incubating CJD, or how many
recipients were now set to die from it. But 27,000 of the world's children
had received injections when the practice was stopped on April 20. As Dr.
Paul Brown of the NIH wrote later that year, America now faced the "ominous
possibility of a burgeoning [CJD] epidemic. (Twenty-two cases have now
been recorded in U.S. hormone recipients, and new ones are still turning
up each year.)
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- Britain faced an epidemic as well, and hormone recipients
were not the only ones at risk. Peter Stent had just lost those nine cows
when the hGH crisis came to light, and other English farmers were soon
having similar experiences. In 1986, pathologists discovered that Pitsham
Farm syndrome was yet another variation on scrapie, kuru and CJD"a
bovine spongiform encephalopathy' or BSE. And when the toll continued to
rise, health officials started considering defensive measures. In 1988,
they mandated the destruction of stricken cows and halted the use of cows,
sheep and other ruminant animals in cattle feed. Unfortunately' they underestimated
the threat they faced.
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- TAINTED FEED
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- BSE was by now so rampant that existing feed supplies
were infecting hundreds of cattle every week. But because most of the infected
cows were still healthy' the epidemic appeared small. Instead of seizing
all potentially tainted feed, the government gave farmers and feedlots
five weeks to use up their inventories. And instead of barring cow and
sheep offal from all feed products, the new rules focused narrowly on feed
intended for British cows. Beef byproducts continued to circulate in pig
and chicken feed, which proved impossible to segregate from cattle feed
on farms and in factories. And because the new rules said nothing about
exports, Britain's banned cattle feed flooded other countries for another
eight years. From 1988 to 1996, Asian nations alone bought nearly a million
tons.
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- Meanwhile, people continued to eat as much beef as ever.
The British government dismissed concerns about the food supply' but there
were soon clear signs that BSE could spread beyond cattle. The disease
started cropping up in zoo animals and domestic cats, which were receiving
beef byproducts in their feed. Then researchers succeeded at transmitting
BSE from a cow to a pig through injections of brain tissue. Each finding
caused a new wave of public concern' forcing the government to adopt new
precautions. By late 1990, health officials had banned a list of highly
infectious cow parts"the brain' spinal cord, spleen' thymus, tonsils
and intestines"from all food products, human or animal. Yet the government
continued to insist that people had no cause to worry.
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- "Beef is one of the great unifying symbols of our
culture. The Roast Beef of Old England is a fetish, a household god, which
has suddenly been revealed as a Trojan horse for our destruction.
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- - THE GUARDIAN
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- Britain's chief medical officer was still denying any
risk in 1993 as Alison Williams, the young Welsh woman' drifted into a
stupor. But everything changed two years later, when pathologists examined
the brains of Williams and several other young adults who had died of what
looked like CJD. In addition to the spongiform vacuoles that are the hallmark
of the disease, their brains were littered with large, flower-shaped plaques.
And their lesions were concentrated not in the cerebral cortex (the usual
locus of CJD damage) but in the cerebellum, a globular structure perched
near the base of the brain. In short, their tissue samples had BSE written
all over them. In 1996, Health Secretary Stephen Dorrell went before Parliament
to announce that BSE had spawned a new human disease: a "variant of
CJD, or vCJD. "Beef is one of the great unifying symbols of our culture,
The Guardian lamented in an editorial. "The Roast Beef of Old England
is a fetish, a household god, which has suddenly been revealed as a Trojan
horse for our destruction.
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- FEWER CASES REPORTED
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- Finally' almost a decade after the first cow got sick,
Britain banned any recycling of farm animals and stopped exporting meat-based
cattle feed. The country has since spent billions destroying cows more
than 30 months old, regardless of their apparent health, and disposing
of the remains. Some 500,000 tons of ground carcass are now stored at 13
sites around the country. Sealed tankers transport the stuff to high-temperature
incinerators. The ashes are then buried. Thanks to these belated efforts,
British farmers are now reporting only 30 BSE cases a week, down from 1,000
or more in the early ,90s.
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- For the rest of the world, the worst almost surely lies
ahead. A dozen European countries have now reported BSE in native-born
cows. Spain and Germany recently saw their first cases, after years of
insisting that their herds had been spared. And the United Nations is urging
non-European countries that imported British offal during the 1980s and
,90s to consider themselves "at risk for BSE and its human variant.
vCJD is still concentrated overwhelmingly in the United Kingdom, home to
89 of the 94 the known cases. But the epidemic is young. France's first
victim, Arnaud Eboli, was a 17-year-old martial-arts enthusiast when he
fell ill three years ago. His mother, Dominique, recalls how he grew ever
more agitated and irritable, often crying and sometimes screaming at her,
"I,m going crazy! I have mad-cow disease! He stopped walking or talking
last May and lost consciousness in August, but his frail shell still occupies
a bed at home. "I don't even remember what he was like anymore, his
mother says.
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- The United States, to its credit, has shown foresight.
Most experts believe we now have the safeguards in place to prevent widespread
outbreaks. In the years since BSE was first recognized, the federal government
has banned feed imports from affected countries, barred the use of domestic
ruminants in cattle feed, even outlawed blood donations by people who spent
more than six months in Britain between 1980 and 1996. Not a single mad
cow has been reported in this country' and consumers seem confident that
the meat they're eating is safe. "We have no indication that consumption
is falling, says Alisa Harrison of the National Cattlemen's Beef Association.
"Actually' beef demand is on the increase.
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- NOT LOOKING HARD ENOUGH?
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- But it's a bit early to conclude that America is prion-proof.
Spongiform encephalopathies have turned up in American sheep, deer, elk,
mink and people in recent decades. And though BSE has not been seen in
U.S. cattle, some experts suspect we,re just not looking hard enough to
find it. Over the past decade, animal-health officials have examined brain
tissue from 12,000 "downer (nonambulatory) cattle without finding
any BSE. Some 2,300 downers tested negative last year"proving, says
Gary Weber of the Beef Association' that the U.S. infection rate is fewer
than one cow in a million. Other experts say he's wrongly assuming that
only downer cattle can have BSE, when infected cows may look healthy for
five years. Germany appeared BSE-free when it tested only downers, says
Marcus Doherr, an epidemiologist who helped design Switzerland's testing
program. "Now, with very intensive screening, they have found over
30 cases within two months.
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- If BSE did show up in this country' could we keep the
disease from spreading? Agriculture officials say the ban on bovine cannibalism
would prevent the kind of explosion Britain experienced early on. Perhaps,
but this country's feed rules are neither as strict nor as well enforced
as you might think. Since cows and sheep are prone to TSEs, the government
bars the use of cow and sheep byproducts in their feed. But since pigs
and poultry don't exhibit TSEs outside the laboratory' they can eat anything.
That's not a problem in itself, unless pigs are more susceptible than we
realize. The trouble is, it's nearly impossible to keep the different products
apart"and a feed kernel the size of a peppercorn can transmit BSE.
From 1988 until 1996, Britain used the current U.S. standard. There was
so much cross-contamination"in rendering plants, in feedlots and in
barnyards"that an estimated 60,000 cattle were infected as a result.
Would that system work any better here? The record isn't encouraging. Just
six weeks ago a Purina outlet in Gonzales, Texas, called a feedlot in Floresville
to explain that an employee had inadvertently spiked a recent shipment
of cattle feed with offal intended only for other animals. More than 1,200
cattle were already munching the stuff when the call came.
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- There is no evidence that the feed was tainted. Even
so, Purina purchased the affected cattle and pledged to keep them out of
the food chain (presumably by destroying them). Purina has also announced
that it will stop using sheep or cattle in any of its products. And the
American Feed Industry Association is now pushing its members to create
separate "production lines within their factories to prevent such
commingling. But these reforms are voluntary' and the feed companies, past
record doesn't inspire confidence. In a study published last fall, the
General Accounting Office found that 20 percent of the 1,700 U.S. companies
handling both restricted and unrestricted offal "did not have a system...
to prevent commingling and cross contamination.
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- TOXIC TONICS?
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- The United States lags in other areas as well. Studies
(and common sense) suggest that brain-destroying prions are more likely
to show up in meat torn from a cow's spinal column than' say' a rump roast.
Though Britain now bars the sale of such high-risk tissues, U.S. law still
permits it (unless the tissue comes from a high-risk country). An American
hot dog, for example, can contain up to 20 percent "mechanically separated
meat, which the government describes as "a paste-like and batter-like
meat product produced by forcing bones with attached edible meat under
high pressure through a sieve ... And because dietary supplements remain
largely unregulated in this country' their manufacturers can peddle the
most potentially dangerous tissues as tonics. Atrium Inc.'s Brain 360 promises
360mg of "raw brain concentrate (bovine). Atrium's Pituitary Whole
provides 40mg of raw pituitary' also from cows. And PhytoPharmica's Adrenal-Cortex
Fractions include raw bovine lung, heart, kidney' spleen and brain' all
in one caplet.
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- Grotesque oddities or public-health threats? It's impossible
to say. We tend to assume the best until confronted with evidence to the
contrary. But if the story of BSE teaches us anything, it's that paranoia
pays. Who would have worried about eating a cheap British burger in 1985?
Who would have deprived a stunted child of a chance to grow tall in the
1960s or ,70s? Wendy Nofi reached nearly five feet with the help of human
growth hormone. She married, had three kids and lived happily in Bethpage,
N.Y., until 1995, when she started losing her balance. "She always
felt like she was on a boat, kind of rocking, her husband, Michael, recalls.
You know the rest of the story. Her vision blurred. She stopped walking
and swallowing and lost all bowel and bladder control. By the time she
died in 1998, she had spent two years on a feeding tube. "There were
absolutely no guidelines for screening the pituitaries, her husband now
marvels. "Really' they didn't screen anything. Of course not. No one
had gotten sick.
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- With Anne Underwood in New York, Adam Rogers in Washington'
Andrew Murrin Los Angeles, Karen Springen in Chicago, William Underhill
and Michelle Chan in London and Scott Johnson in Paris
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- © 2001 Newsweek, Inc.
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