Experimental assessment of the pathogenicity of H5N1 influenza A viruses isolated in Japan.
We examined the pathogenicity for chickens of two H5N1 avian influenza viruses isolated in Japan, A/chicken/ Yamaguchi/7/2004 (Ck/Yamaguchi/7/04) isolated from outbreaks in commercial layer chickens, and A/duck/Yokohama/aq10/ 2003 (Dk/Yokohama/aq10/03) isolated from duck meat imported from China. All chickens inoculated intranasally with either strain died, and the viruses were reisolated from all organs examined. However, both the mean time of onset of clinical signs and the mean death time of Ck/Yamaguchi/7/04 were shorter than those of Dk/Yokohama/aq10/03.
Mase
Masaji
M
Department of Infectious Diseases, National Institute of Animal Health, 3-1-5 Kannondai, Tsukuba, Ibaraki 305-0856, Japan.
Imada
Tadao
T
Nakamura
Kikuyasu
K
Tanimura
Nobuhiko
N
Imai
Kunitoshi
K
Tsukamoto
Kenji
K
Yamaguchi
Shigeo
S
D000281:Administration, Intranasal; D000818:Animals; D002642:Chick Embryo; D002645:Chickens / Q000821:virology*; D002681:China; D004372:Ducks / Q000821:virology; D053124:Influenza A Virus, H5N1 Subtype / Q000145:classification / Q000302:isolation & purification* / Q000472:pathogenicity*; D005585:Influenza in Birds / Q000209:etiology / Q000821:virology*; D007564:Japan; D013045:Species Specificity; D013997:Time Factors; D014774:Virulence