West Nile Virus may be new deadly strain, USGS tell...( Recent crow die-offs suggest the ...)

Recent crow die-offs suggest the West Nile virus which emerged in New York in late August could be more deadly to North American bird species than to species in Africa, the Middle East and Europe, where the virus is normally found, a USGS scientist reported today at a congressional field hearing held in Connecticut by the Senate Committee on Environment and Public Works.

Dr. Robert G. McLean, director of the USGS National Wildlife Health Center in Madison, Wis., briefed the committee on the role of native bird populations and other wildlife in the emergence of West Nile virus in the United States. Detection of the virus in birds and other animal species provides critical information to public health agencies tracking the infection in people.

"The high mortality in crows and other bird species is unusual for these viruses," McLean said. "This suggests that this virus is more virulent to our native birds or it may represent a new, more virulent strain of the virus."

Resident and migratory birds may play an important role in natural transmission of the virus and in maintaining the virus in the United States, McLean testified. "Migratory birds could also spread the virus to other states outside of the New York City area," he said. "Enhanced monitoring through surveillance for early, rapid detection of West Nile virus in states outside the affected area will be important to guide prevention measures."

The emergence of West Nile virus in the United States, which led to the deaths of seven people from West Nile encephalitis, has brought together the combined expertise and resources of many federal and state agencies along the eastern seaboard. Several federal and state agencies and private groups are searching for stored human and animal specimens that were collected prior to 1999 in order to test them for the presence of West Nile virus. These specimens are also being tested for antibodies to determine if the viru
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Contact: Paul Slota
paul_slota@usgs.gov
608-270-2420
United States Geological Survey
13-Dec-1999