Isolation and molecular characterization of equine H3N8 influenza viruses from pigs in China.
During 2004-2006 swine influenza virus surveillance, two strains of H3N8 influenza viruses were isolated from pigs in central China. Sequence and phylogenetic analyses of eight gene segments revealed that the two swine isolates were of equine origin and most closely related to European equine H3N8 influenza viruses from the early 1990s. Comparison of hemagglutinin (HA) amino acid sequences showed several important substitutions. One substitution caused the loss of a potential glycosylation site, and two substitutions, located at the cleavage site and adjacent to the receptor-binding pocket, respectively, had been reported previously in canine H3 HAs. This expansion of host range of equine H3N8 influenza viruses with mutations in the HA protein might raise the possibility of transmission of these viruses to humans.
Tu
Jiagang
J
Unit of Animal Infectious Diseases, National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, 430070 Wuhan, People's Republic of China.
Zhou
Hongbo
H
Jiang
Taozhen
T
Li
Chun
C
Zhang
Anding
A
Guo
Xuebo
X
Zou
Wei
W
Chen
Huanchun
H
Jin
Meilin
M
D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D000818:Animals; D002681:China / Q000453:epidemiology; D019143:Evolution, Molecular; D005814:Genes, Viral; D016679:Genome, Viral; D019267:Hemagglutinin Glycoproteins, Influenza Virus / Q000235:genetics; D053123:Influenza A Virus, H3N8 Subtype / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D008969:Molecular Sequence Data; D009154:Mutation; D009976:Orthomyxoviridae Infections / Q000453:epidemiology / Q000662:veterinary* / Q000821:virology; D010802:Phylogeny; D012367:RNA, Viral / Q000235:genetics; D016415:Sequence Alignment; D013552:Swine / Q000821:virology*; D013553:Swine Diseases / Q000453:epidemiology / Q000821:virology*
D019267:Hemagglutinin Glycoproteins, Influenza Virus; D012367:RNA, Viral