Flu fears
force killing of Delaware birds
PHILADELPHIA, Feb 7 (Reuters) _ A flock of 12,000 chickens in Delaware was
destroyed on Saturday in a bid to prevent the spread of avian flu, and state
agriculture officials hastened to say the virus differs from the one that has
killed people in Asia.
The chickens were slaughtered on a farm in southern Kent
County, Delaware, at 11:30 a.m. (1630 GMT) after two birds tested positive for
the virulent H7 virus on Friday, Delaware agriculture secretary Michael Scuse
said.
The virus is different from the H5N1 virus in Asia, Scuse
said. That strain has forced the slaughter of millions of birds there and killed
18 people in Thailand and Vietnam who had come into direct contact with
them.
"The virus that is in Asia is a mutation of H5," Scuse
said. He said the H7 strain found in Delaware is fatal to poultry but does not
transmit to humans.
Scuse said he was "fairly confident" the virus had not
spread. As a safeguard, however, other flocks within a two-mile (3.2 km) radius
of the infected farm would be tested, and the outcome of that process would
probably be known by Tuesday, he said.
If the virus is found in any of the other flocks, the
testing area would be extended to five miles (8 km), he said.
The slain flock's carcasses will be composted at the
farm, which has been quarantined, he said.
South Korea, which is battling a deadly outbreak of the
virus, reacted swiftly to reports of the discovery in Delaware, immediately
halting imports of U.S. poultry.
Poultry is a multibillion-dollar industry in the Delmarva
Peninsula where the infected farm is located, and is the mainstay of the local
economy. The Delmarva region, which lies between the Chesapeake Bay and the
Atlantic Ocean, consists of parts of Delaware, Maryland and Virginia.
The farmer did not supply chickens to Purdue or any other
commercial poultry company, said Anne Fitzgerald, a spokeswoman for the Delaware
Agriculture Department.
The Delaware case would not be the first time the H5
strain, or the so-called "low-pathogenic" virus, has hit the poultry sector in
the United States, he said.
An outbreak of a related strain of bird flu in the
northeastern United States in 1983 and 1984 forced more than 17 million birds to
be destroyed, the USDA said. That incident also caused retail egg prices to soar
by more than 30 percent.
Minnesota revs up bird flu prevention
plan
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Joy Powell, Star
Tribune |
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Published
February 7, 2004 |
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André Ziegler deftly sliced into the body cavity of a turkey to peer at the
bright pink lungs, the mahogany-colored liver and other tiny organs, searching
for disease before it has a chance to spread through flocks.
He's a top poultry pathologist at the University of Minnesota's Veterinary
Diagnostic Laboratory in St. Paul -- and a point guard in the state's full-court
press against diseases such as the deadly avian influenza that's sweeping
through 10 Asian countries, killing millions of chickens and at least 16
people.
All influenza viruses can change, and experts say "bird flu," as it's
commonly known, could pose a deadly global threat if it becomes easily
transmissible between humans.
For decades, the university, the Minnesota Board of Animal Health and the
industry have pushed hard to protect the state flocks from such insidious
killers, and for good reason: Minnesota leads the rest of the nation in turkey
production, generating about $600 million in income for farmers, processors and
related industries each year.
Now, the state will ramp up its surveillance with new, highly sensitive
molecular tests under a contract awarded by the U.S. Department of Agriculture,
said Prof. Jim Collins, director of the Veterinary Diagnostic Laboratory in St.
Paul. That program targets avian influenza and Exotic Newcastle viruses, which
have cost the U.S. poultry industry hundreds of millions of dollars in recent
decades, he said.
The amount the University of Minnesota will receive depends on the number of
tests conducted, he said. Though most of the contracts went to Southern states,
Minnesota's animal health and USDA officials convinced federal officials that
the state should be included because of the importance of its poultry
industry.
Aside from being the turkey leader, Minnesota is home to Gold'n Plump of St.
Cloud, the Upper Midwest's biggest chicken processor. The state's broiler
chickens generate nearly $100 million in economic activity each year. Egg
production was valued at $106 million in 2002.
Avian influenza has led to the deaths of thousands of birds in Minnesota
after breaking out in less-virulent forms here over the years.
"It's a problem that's been well recognized in this country," Ziegler said of
bird flu. "We've been bitten by it a few times, and we've learned some valuable
lessons from that."
For instance, a good surveillance network must be in place long before a
disease outbreak -- something he said Minnesota has done well.
In Asia, where humans, fowl and other livestock live in close proximity and
sometimes share ponds, there are no comprehensive surveillance systems. On
Thursday, global animal and human health experts in Rome and Washington, D.C.,
called for better surveillance and targeted vaccination of poultry in the most
heavily affected countries.
Minnesota is vulnerable because as the land of 10,000 lakes, it has millions
of waterfowl that could serve as hosts for the virus and pass it on. That's one
reason that experts such as Dave Halvorson of the University of Minnesota
Extension Service persuaded most of the industry to switch from raising turkeys
on open ranges to inside bio-secure barns years ago.
Avian influenza, first identified a century ago in Italy, jumped species to
begin killing humans in 1997, when six people died in Hong Kong.
There are roughly 15 subtypes of the avian influenza virus, with about 250
various genetic combinations, and all can sicken turkeys. The type ravaging
Asia's flocks is highly infectious among birds, and now the fear is that the
virus could change and cause a pandemic among humans.
Two subtypes, called H7 and H5, are generating the highest concern because
they can evolve into the highly pathogenic, or virulent forms.
"These things can mutate, and they can do it very quickly," Ziegler said.
"They can literally do it overnight."
In Asia's outbreak, an H5 type has killed people in Vietnam and Thailand
after victims came in contact with infected birds or surfaces contaminated by
their manure, according to the World Health Organization.
Culling the flocks
Culling the sick birds is crucial in preventing pandemics, which occur when
the mutating virus begins spreading rapidly among people, WHO experts say.
Historical patterns indicate that influenza pandemics can be expected to occur,
on average, three times each century.
There were three pandemics in the 20th century, and all spread worldwide
within a year of detection. The last was the Hong Kong flu, which killed about
34,000 people in the United States in 1968 and 1969.
"Obviously we're watching it from a production standpoint," said Steve Olson,
a spokesman for Minnesota's poultry industries, "but the risk of this becoming a
human health problem in the United States is low."
In Asia, economists say that if the disease spreads beyond the 50 million
birds already destroyed, it could cost the affected regions billions of
dollars.
Halvorson, who travels the world to lecture about avian health, said public
hysteria could hurt the U.S. market if there is an outbreak of bird flu.
He and others say Minnesota has a number of firewalls in place to contain any
outbreak. With the voluntary help of the industry, flocks are closely monitored
and the birds' blood sampled to identify and contain any disease.
The influenza virus also can be spread by manure on the bottom of shoes of
people who visit cockfighting farms or the live-bird markets that sell poultry
for ethnic cooking, Halvorson said.
Kevin Elfering, head of dairy, food and meat inspections for the Minnesota
Agriculture Department, said he suspects there are cockfighting enterprises in
Minnesota, where it's illegal.
Nationwide, live-bird marts for chickens, ducks and other fowl that are
killed and dressed on the spot have been identified as hotspots where viruses
linger on crates and other equipment, Ziegler said.
"It's a great mixing vessel for those viruses, and once they take a foothold,
God only knows where they go," he said.
Such live-bird markets deal with small poultry farmers from throughout a
region. Those farmers sell untested birds from a variety of sources, which then
mingle with one another, Ziegler said.
USDA officials continue to grapple with the problem, trying to stop such live
poultry sales at markets in New York City and elsewhere. Minnesota has at least
three such markets in the metro area, Elfering said.
In Minnesota's recent history, there have been only isolated outbreaks of
lower-grade avian influenza that are quickly contained, Olson said.
"We've been able to control it through a combination of a surveillance
program with the Board of Animal Health and research at the University of
Minnesota," he said.
Joy Powell is at jpowell@startribune.com