Submitted to: Meeting Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 6/17/2017
Publication Date: 8/27/2017
Citation: Swayne, D.E. 2017. Infectivity, transmission and pathogenicity of avian influenza viruses for domestic and wild birds. Proceedings of The 33rd World Veterinary Congress in Seoul, Korea, August27-31, 2017. p.438-441.
Technical Abstract: Individual avian influenza (AI) virus strains vary in their ability to infect, transmit and cause disease and death in different bird species. Low pathogenicity AI (LPAI) viruses are maintained in wild birds, and must be adapted to pass to domestic poultry, where they replicate in respiratory and intestinal tracts causing low mortality rates. High pathogenicity AI (HPAI) viruses arise from mutation in the hemagglutinin of H5 or H7 LPAI viruses while circulating in terrestrial poultry. HPAI viruses typically produce a severe, systemic disease with high mortality in chickens and other galliforme birds. However, these same HPAI viruses usually produce no infection or only mild disease in domestic ducks and other wild aquatic birds. Some HPAI viruses have increased in virulence for chickens as evident by shorter mean death times (MDT) and a greater propensity for massive replicate in vascular endothelial cells. Recently, the H5N1 Goose/Guangdong-lineage HPAI viruses have changed from producing inconsistent respiratory infections in 2 week-old domestic ducks to some strains being highly lethal with virus in internal organs and brain.