id	author	title	date	pages	extension	mime	words	sentences	flesch	summary	cache	txt
cord-000114-f0vud3gu	Kim, Jeong‐Ki	Ducks: The “Trojan Horses” of H5N1 influenza	2009-05-31		.txt	text/plain	5413	313	51	While the H5N1 HPAI viruses are 100% lethal to chickens and gallinaceous poultry, they often cause asymptomatic infection in some species of domestic and wild ducks. 37 The first indication of the spread of H5N1 HPAI viruses from domestic to wild species of aquatic birds occurred in Kowloon and Penfold Park in Hong Kong, 38 where 19 different duck species were infected. If these wild birds are migratory and experience limited morbidity, they in turn can disperse HPAI viruses widely (Figure 2) , as suggested by the high genetic similarity of HPAI isolates from Africa, Europe, and the Middle East to the Qinghai-H5N1 virus. There is consensus that the migratory waterfowl of the world (predominantly wild ducks) serve as the natural reservoirs of all influenza A viruses, which cause asymptomatic infection in these birds. 51 The continuing co-circulation of multiple subtypes of LPAI viruses in domestic poultry could explain why a small percentage of susceptible domestic species can appear healthy while shedding transmissible levels of H5N1 HPAI virus.	./cache/cord-000114-f0vud3gu.txt	./txt/cord-000114-f0vud3gu.txt