Antigenic and genetic characteristics of H1N1 human influenza virus isolated from pigs in Japan.
Two strains of influenza A virus were isolated from pigs in northern Japan in 1992. Serological tests showed that the haemagglutinin (HA) and neuraminidase (NA) antigens were more closely related to those of recent human H1N1 viruses than to those of swine H1N1 viruses. The HA and NA genes of isolate A/sw/Obihiro/5/92 were shown to be closely related to those of current human H1N1 viruses. Evolutionary trees constructed from nucleotide sequences showed that the HA and NA genes of A/sw/Obihiro/5/92 were apparently on a branch cluster containing human strains isolated between 1990 and 1992.
Katsuda
K
K
Department of Veterinary Microbiology, Obihiro University of Agriculture and Veterinary Medicine, Hokkaido, Japan.
Sato
S
S
Shirahata
T
T
Lindstrom
S
S
Nerome
R
R
Ishida
M
M
Nerome
K
K
Goto
H
H
D000818:Animals; D001483:Base Sequence; D019267:Hemagglutinin Glycoproteins, Influenza Virus; D006389:Hemagglutinins, Viral / Q000235:genetics / Q000276:immunology; D053118:Influenza A Virus, H1N1 Subtype; D009980:Influenza A virus / Q000235:genetics / Q000276:immunology*; D007564:Japan; D008969:Molecular Sequence Data; D009439:Neuraminidase / Q000235:genetics / Q000276:immunology; D013552:Swine / Q000821:virology*
D019267:Hemagglutinin Glycoproteins, Influenza Virus; D006389:Hemagglutinins, Viral; D009439:Neuraminidase