|
 But some wildlife experts are skeptical of suggestions that wild
birds are responsible for spreading the H5N2 flu strain that has
infected poultry in Minnesota, Missouri and Arkansas.
A top investigator from the U.S. Department of Agriculture (USDA)
says that testing performed by the government supports a conclusion
that the virus is being carried by waterfowl along an established
migratory route that stretches south from Minnesota to the Gulf of
Mexico. The virus can be transmitted to poultry from ducks through
droppings that land on farms or when birds interact, among other
ways.
"That's the way we're sort of pointing right now: to ducks as the
problem," said Brian McCluskey, lead epidemiologist for the U.S.
Department of Agriculture's Animal and Plant Health Inspection
Service. The agency has not, however, identified how the disease
made its way from the ducks to domestic fowl.
Experts who doubt that wild birds are spreading the virus note that
the disease has moved from Minnesota in the north, south to Arkansas
and Missouri, the opposite direction birds migrate through the area
in the spring.
"When you're talking about where I would put my money, I would say
that north to south movement in the beginning of March totally does
not make sense," said Hon Ip, a microbiologist for the National
Wildlife Health Center.
Determining how avian flu is spreading is crucial to preventing
future outbreaks, protecting poultry and limiting damage in the $5.7
billion export market. Already, the outbreak has prompted top
poultry importers, including Mexico and Canada, to widen trade
restrictions.
Previous outbreaks on the West Coast were linked to wild fowl by the
USDA. But the virus can be spread in other ways, too, including
through contaminated trucks, humans or animal feed. People can carry
infected material, such as feces or even feathers, to farms on their
clothes, shoes or vehicles.
Once it arrives, avian flu can spread rapidly through a flock,
killing birds in as little as 24 hours. The virus has not been
identified in humans and is not expected to pose a public health
risk, according to the USDA.
The infection in a Minnesota turkey flock was the first along the
migratory route known as the Mississippi flyway, which also includes
Missouri and Arkansas -- and continues southeast toward the major
chicken producing states of Mississippi and Alabama.
After the Minnesota case was identified on March 5, the USDA
organized a call to advise state veterinarians along the route that
the virus could be headed in their direction, said Richard Fordyce,
director of Missouri's Department of Agriculture.
But wildlife experts question whether wild birds are moving the
virus along the flyway.
[to top of second column] |
"It is extraordinarily unlikely that avian influenza in the turkey
flock in Minnesota has anything to do with wild birds," said Lou
Cornicelli, wildlife research manager for the Minnesota Division of
Fish and Wildlife . He noted that few migratory ducks have started
arriving in Minnesota.
"I would think the investigation is going to look more toward the
biosecurity issue with food or transport," Cornicelli added. "The
fact that there are no ducks here would indicate that it's not ducks
in Minnesota."
One day after the USDA confirmed avian flu in Minnesota, state
wildlife employees took a low-level airplane flight to scout a
15-mile radius around an infected turkey farm for wild birds that
could have carried the virus.
They spotted just 18 swans and 100 ducks, and they appeared to be
"city birds" that do not migrate, Cornicelli said. The state
nevertheless tested feces from some of the ducks for avian flu, but
the results were negative.
Arkansas officials doubt the role of migratory birds in their
state's outbreak, too, partly because the area with the infected
farm does not attract many wild birds and waterfowl, said Karen
Rowe, bird conservation program leader for the Arkansas Game & Fish
Commission.
Most birds in Arkansas are flying north at this time of year, Rowe
added. She plans to travel to the farm next week to look for clues
about how the virus could have spread.
"Was it carried in on clothing or boots? There's just a lot of
unanswered questions," Rowe said.
Butterball LLC, which has contracts to buy turkeys from farms in
Arkansas and Missouri that were infected, declined to speculate
about how the virus was spread.
Cargill Inc [CARG.UL] contracts for turkeys from an infected farm
near Fortuna, Missouri, and said the origin of that infection is
under investigation.
"We know that AI is spread by migratory wild waterfowl," spokesman
Michael Martin said, referring to the virus. "However, we are not
taking anything for granted."
(Reporting by Tom Polansek, Editing by Jo Winterbottom and Sue
Horton)
[© 2015 Thomson Reuters. All rights
reserved.] Copyright 2015 Reuters. All rights reserved. This material may not be published,
broadcast, rewritten or redistributed. |
