الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Influenza virus belongs to the Orthomyxovirus family and contains 8 different segments of negative-stranded RNA. There are 3 types: A, B, and C, distinguishable by internal virus proteins. Influenza A is responsible for most human influenza disease, causes avian influenza, and is the source of all past influenza pandemics in humans. Influenza B is a disease of humans only, while influenza C causes milder illness in both humans and swine and occurs uncommonly. Avian influenza viruses that cause HPAI are highly virulent and mortality rates in infected flocks often approach 100%. All known subtypes of influenza A can be found in birds, but only subtypes H5 and H7 have caused HPAI outbreaks. Avian influenza is a highly contagious viral infection of birds. Some avian influenza viruses, called highly pathogenic avian influenza (HPAI) viruses, can cause sudden, high mortality (up to 100%) in domestic fowl (chickens) and turkeys. Recent severe and widespread epidemics of HPAI in Europe in 2003 and in East Asia in 2004/5 have heightened awareness of the ongoing risk to Australia’s bird population