Avian influenza, mallards - USA (MD)(02): LP, USDA report

International Society for Infectious Diseases
<http://www.isid.org>

Source: Official USDA release [edited]
< http://www.usda.gov/wps/portal/!ut/p/_s.7_0_A/7_0_1OB?contentidonly=true&contentid=2006/09/0348.xml>

Release No. 0348.06
Contact: Angela Harless, USDA (202) 720-4623
DOI Press Office (202) 208-6416

Avian Influenza Tests Complete On Maryland Resident Wild Mallard Ducks
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The U.S. Departments of Agriculture and Interior today announced
final test results that confirm that an H5N1 avian influenza virus
detected in fecal samples collected last month from resident wild
mallard ducks in Maryland is a low-pathogenic subtype. This strain
has been detected several times in wild birds in North America and
poses no threat to human health.

The USDA National Veterinary Services Laboratories (NVSL) confirmed
the presence of the "North American strain" of low-pathogenic H5N1
avian influenza through virus isolation in samples collected from the
resident wild mallards in Queen Anne's County, Maryland. Test results
announced on 1 Sep 2006 indicated that an H5N1 avian influenza
subtype was present in 9 of the collected samples, but further
testing was necessary to confirm pathogenicity. As previously
announced, genetic testing ruled out the possibility that the samples
carried the specific highly pathogenic strain of H5N1 avian influenza
that is circulating overseas.

Low pathogenic strains of avian influenza commonly occur in wild
birds and typically cause only minor sickness or no noticeable signs
of disease in birds. Low-pathogenic H5N1 is very different from the
more severe highly pathogenic H5N1 circulating in parts of Asia,
Europe and Africa. Highly pathogenic strains of avian influenza
spread rapidly and are often fatal to chickens and turkeys.

The Departments of Agriculture and Interior are working
collaboratively with States and academic institutions to sample wild
birds throughout the United States for the presence of highly
pathogenic avian influenza. More than 21 000 wild birds have been
tested so far this year and none have been infected with highly
pathogenic avian influenza.

For more information about the collaborative avian influenza efforts go to
<http://www.usda.gov/birdflu>
<http://www.doi.gov/issues/avianflu>
or the U.S. Government's Web site for avian influenza and human
pandemic preparedness at
<http://www.avianflu.gov>