Submitted to: Wildlife Disease Association Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 7/12/2007
Publication Date: 8/12/2007
Citation: Brown, J.D., Swayne, D.E., Stallknecht, D.E. 2007. Comparative susceptibility of waterfowl and gulls to highly pathogenic avian influenza H5N1 virus [abstract]. In: Proceedings of the Annual Meeting of the Wildlife Disease Association, August 12-17, 2007, Estes Park, Colorado. p. 29.
Technical Abstract: Wild avian species in the Orders Anseriformes (ducks, geese, swans) and Charadriiformes (gulls, terns, shorebirds) have traditionally been considered the natural reservoirs for avian influenza viruses (AIV) and morbidity or mortality is rarely associated with AIV infection in these hosts. However, since 2002 highly pathogenic avian influenza (HPAI) H5N1 viruses have caused mortality in numerous wild avian species throughout Eurasia. Based on mortality data from field reports, some of these viruses are highly virulent for certain species of anseriforms. In this study, thirteen species of anseriforms and charadriiforms were inoculated intranasally with A/Whooper Swan/Mongolia/244/05 (H5N1) avian influenza virus (AIV) to evaluate the range of viral shedding and pathology within these two avian orders. Species-related differences in morbidity, mortality, viral shedding, and pathology exist between the examined species. Based on mortality and the distribution of virus, these species were separated into three general categories: 1) 100% mortality with viral antigen disseminated in the vasculature and/or parenchyma of numerous visceral organs, 2) high mortality with antigen primarily distributed in the brain, pancreas, adrenal glands and/or heart, and 3) No mortality and no viral antigen was detected. Where possible, the majority of our experimental infection results are consistent with field data from H5N1 HPAI virus outbreaks. Species-related differences in susceptibility and viral shedding are vital to understanding the epidemiology of H5N1 HPAI virus in wild waterfowl and in developing control efforts, biosecurity plans, and surveillance needs worldwide.