Submitted to: Western Poultry Disease Conference
Publication Type: Proceedings
Publication Acceptance Date: February 4, 2003
Publication Date: March 8, 2003
Citation: Spackman, E., Suarez, D.L. 2003. Evaluation Of Molecular Markers For Pathogenicity In Recent H7N2 Avian Influenza Isolates From The Northeastern United States. Western Poultry Disease Conference. Interpretive Summary: Intrepretive summary not required.
Technical Abstract: Since 1994 H7N2 subtype avian influenza viruses (AIV) have been routinely isolated from the urban live bird markets (LBM's) in New York and northern New Jersey. As illustrated by several recent outbreaks of H7N2 AIV since 1997 in commercial poultry in Pennsylvania and Virginia linked to the LBM's, there is a constant threat for the transmission of the AIV in the LBM's to commercial poultry. The live-bird market system also provides a unique environment for the evolution of AIV due to poor bio-security and the routine intermingling of waterfowl and gallinaceous poultry, natural and non-natural hosts for AIV respectively. Continued circulation of AIV in the LBM system for the past eight years has allowed for the virus to evolve and become adapted to replication in poultry. Historically mildly pathogenic AIV has become highly pathogenic during circulation in poultry, in some cases within months to a few years after initial detection. This indicates that if the virus persists long enough in poultry it may become highly pathogenic. In order to determine the potential for the LBM H7N2 AIV lineage to become highly pathogenic, molecular markers in the hemagglutinin gene that correlate with pathogenicity were evaluated.