Submitted to: World Veterinary Poultry Association Congress Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 7/11/2007
Publication Date: 9/10/2007
Citation: Swayne, D.E. 2007. Changing face of avian influenza ecology and its control: From wild birds to poultry and back again. In: Proceedings of the XV Congress of the World Veterinary Poultry Association, September 10-16, 2007, Beijing, China. CD-ROM.
Technical Abstract: Twenty-five epizootics of high pathogenicity avian influenza (HPAI) have occurred in the world since 1959. The largest of these outbreaks has been the H5N1 HPAI which has caused problems in poultry and some wild birds in over 57 countries of Asia, Europe and Africa since beginning in 1996. The H5N1 HPAI viruses have also caused severe infections and death in a few humans, but such infections have been rarely caused by other HPAI viruses. Natural infections of wild birds with HPAI virus was first reported in common terns in South Africa during 1961 with the H5N3 subtype. With the H5N1 HPAI virus first reported in China during 1996, wild bird infections were not initially reported, but beginning in 2002 in Hong Kong, a variety of fatal infections in various wild and captive waterfowl and wading birds was reported. In early 2005, large die-offs of wild waterfowl were reported in Qinghai China, followed by wild bird mortality in Mongolia and Siberia. The outbreaks were also reported in poultry in Siberia and Kazakhstan. In winter 2006, mortality was identified in waterfowl in several European Union countries with minimal cases in poultry. The HPAI viruses cause severe systemic infection in multiple poultry species and the viruses can be present in multiple internal organs, meat, eggs, and blood. The most recent viruses from Vietnam also cause high mortality in young domestic ducks.