Scientists say Disease infected creatures flying in from Latin America
Pastor Dale Morgan
*Scientists say Disease infected creatures flying in from Latin America*
By LIBBY QUAID, AP Food and Farm Writer
December 5, 2006 02 19 PM
(12-04) 14:19 PST WASHINGTON, (AP) --
Birds from Latin America — not from the north — are most likely to bring
deadly bird flu to the main U.S., researchers said Monday, suggesting
the government might miss the H5N1 virus because biologists have been
looking in the wrong direction.
The United States' $29 million bird flu surveillance program has focused
heavily on migratory birds flying from Asia to Alaska, where researchers
this year collected tens of thousands of samples from wild birds nesting
on frozen tundra before making their way south.
Those birds present a much lower risk than migratory birds that make
their way north from South America through Central America and Mexico,
where controls on imported poultry are not as tough as in the U.S. and
Canada, according to findings in the latest Proceedings of the National
Academy of Sciences.
Nations south of the U.S. import hundreds of thousands of chickens a
year from countries where bird flu has turned up in migratory birds or
poultry, said A. Marm Kilpatrick, lead author of the study.
"The risk is actually higher from the poultry trade to the Americas than
from migratory birds," said Kilpatrick, of the Consortium for
Conservation Medicine in New York. Other researchers on the study came
from the Smithsonian Institution.
If bird flu arrives in Mexico or somewhere farther south, it could be a
matter of time before a migratory bird carries the virus to the United
States, Kilpatrick said.
"It's not just a matter of worrying about who you trade with, but it's a
matter of thinking about who do your neighbors trade with, and who do
your trading partners trade with," Kilpatrick said. "We need to be
looking both south and north."
The study concluded that "current American surveillance plans that focus
primarily on the Alaskan migratory bird pathway may fail to detect the
introduction of H5N1 into the United States in time to prevent its
spread into domestic poultry."
The report is the first to combine the DNA fingerprint of the H5N1 virus
in different countries with data on the movement of migratory birds and
commercial poultry in those countries.
The analysis helped to determine, for example, that the outbreak of bird
flu in Turkey likely didn't come from poultry imports from Thailand, as
previously thought. Instead, the probable source was migratory birds in
Russia, where the virus had similar DNA to the virus in Turkey.
The study found that:
_ Bird flu was spread through Asia by the poultry trade.
_ Most of the spread throughout Europe was from migratory birds.
_ Bird flu spread into Africa from migratory birds as well as poultry trade.
U.S. officials cautioned that the study is not the final authority on
the spread and prevention of bird flu.
"When you look at scientific literature, it's a big puzzle. This puts in
a few more pieces," said David Swayne, director of the Agriculture
Department's Southeast Poultry Research Laboratory in Athens, Ga.
Swayne cautioned that researchers looked only at countries' import
restrictions through 2005.
"I'm not saying it's the fault of the study; the study is designed to
look at what happened in the past," Swayne said. "We have to be very
careful not to over-interpret. There is a limit on how recent the data is."
In addition, Agriculture Department officials said they are not focusing
exclusively on Alaska.
More resources have been spent in Alaska than in other states so far,
but testing is happening throughout the lower 48, and the U.S. is even
helping Mexico do surveillance, said Tom DeLiberto, the department's
National Wildlife Disease Coordinator.
"We have more information now than we did when we designed the
surveillance effort last fall," DeLiberto said.
"We knew that we had limited information and couldn't design a system
that looked at just Alaska," he said. "You have to build a robust system
that could cover a lot of different potential pathways. We know as we
get more information, we'll adapt our system."
Since the deadly H5N1 virus emerged in Hong Kong in 1996, at least 154
people have died and hundreds of millions of chickens, ducks, geese and
turkeys have died or been killed to keep it from spreading.
So far, the virus has killed mostly people who had close contact with
sick birds or their droppings, but scientists fear the virus could
someday mutate into a form that spreads easily among people.
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On the Web:
Proceedings of the National Academy of Sciences:
Agriculture Department: