Researchers have been monitoring the spread of a potentially deadly strain of avian influenza overseas. Health officials worry the H5N1 strain could mutate into a form that could infect humans. Some researchers say the virus could make its way to the United States as early as this fall… by way of wild migratory birds. The GLRC’s Christina Shockley reports:
Researchers have been monitoring the spread of a potentially deadly
strain of avian influenza overseas. Health officials worry the H5N1
strain could mutate into a form that could infect humans. Some
researchers say the virus could make its way to the United States as early
as this fall… by way of wild migratory birds. The GLRC’s Christina
Wild birds carry all sorts of influenza viruses. Most are of no threat to
people, but the H5N1 strain is different. When it gets into people… it’s
often fatal. Overseas the strain has killed whole farms of poultry such as
chicken and ducks… it’s also infected other types of animals, including
The H5N1 strain has not been found in the United States, but most
experts say it’s just a matter of time before it is. Some say infected
domestic poultry or smuggled pet birds will likely bring the virus to the
U.S. Others say the virus could come here by way of migrating birds…
that are on the move now.
Steve Schmitt is the lead veterinarian for Michigan’s Department of
Natural Resources. He says birds from Asia… that are possibly infected
with the H5N1 strain are on their way to Alaska right now. There, they
could mingle with birds that will later fly back to the United States.
Schmitt says there are four major flyways over the U.S.… the Pacific,
central, Mississippi, and Atlantic.
“There are birds that will winter in Asia and then come back and nest in
Alaska. If they bring the virus back with them, then they could transmit
that to birds that are in Alaska that come down any of these four major
flyways, and that of course is a big concern, moving it all over the
Schmitt says most birds that nest in Alaska use the Pacific flyway along
the Pacific coast… to migrate south to the U.S. and Mexico. He says
that means, if the virus were to come to the United States via migratory
birds, the pacific coast would probably be its first stop in the lower 48.
Schmitt says then, birds that use the other flyways could become
“Most of the migration is north-south, but you do have a few that will
move – jump over to another flyway, and when that happens, the
potential to move the virus to that new flyway happens. Once it’s in a
new flyway, that north-south movement would take over.”
Programs are underway an Alaska and throughout the United States to
test wild birds for various strains of avian influenza, including H5N1.
Experts say waterfowl and shore birds are the most likely carriers of the
dangerous strain, but some say land birds – such as migrating songbirds –
should be tested, too.
(Sound of birds)
Julie Craves studies land birds at the Rouge River Bird Observatory on
the University of Michigan’s Dearborn campus. She catches and bands
thousands of wild birds each year during their spring and fall migrations.
This year, Craves will participate in a study that hopes to eventually test
hundreds of thousands of birds across the U.S. and Latin America for
avian flu strains.
“It’s just a great opportunity with people handling birds already, we may
find out some very interesting things about which subtypes are present in
land birds, and if indeed this disease does come to North America, we
will have a head start on seeing what types of migratory pathways are
being used by birds.”
Craves says very little is known about how avian flu moves among land
birds, and experts say each time the virus is transmitted to a different
species it mutates, and each time it mutates, the chances are greater that
it will change into a form that’s easily passed among humans. That’s a
big concern, because such a mutation could lead to a quick spread of
human cases across the globe.
But some say that might never occur… they say the strain might be
unable to mutate into one that’s dangerous to humans.
Arnold Monto is a professor of epidemiology at the University of
Michigan. He says there will be a problem if the strain mutates, but it’s
unlikely people will get the virus from migrating birds.
“I doubt very much whether we’re even gong to see even a handful of
cases in the United States, should avian influenza arrive, and it probably
will, with the migratory birds coming down from Alaska, perhaps next
Monto says most of the human transmissions overseas have been from
poultry being raised in the back yard, and not from wild birds. That
means visiting the ducks and geese in the park… and feeding songbirds
in the back yard… are not high-risk activities. Monto says people should
take basic precautions, such as washing hands, to avoid contracting any
sort of flu virus.
Many experts say, on the list of things to worry about, catching a deadly
form of avian influenza is no where near the top of the list of dangers.
For the GLRC, I’m Christina Shockley.