Isolation and identification of swine influenza recombinant A/Swine/Shandong/1/2003(H9N2) virus.
Ten influenza virus isolates were obtained from infected pigs from different places in Shandong province showing clinical symptoms from October 2002 to January 2003. All 10 isolates were identified in China's National Influenza Research Center as influenza A virus of H9N2 subtype. The complete genome of one isolate, designated A/Swine/Shandong/1/2003(H9N2), was sequenced and compared with sequences available in GenBank. The results of analyses indicated that the sequence of A/Swine/Shandong/1/2003(H9N2) was similar to those of several chicken influenza viruses and duck influenza viruses recently prevalent in South China. According to phylogenetic analysis of the complete gene sequences, A/Swine/Shandong/1/2003(H9N2) possibly originated from the reassortment of chicken influenza viruses and duck influenza viruses. It was found that the amino acid sequence at the HA cleavage site in Sw/SD/1/2003 is R-S-L-R-G, differing clearly from that of other H9N2 subtype isolates of swine influenza and avian influenza, which is R-S-S-R-G.
College of Animal Science, Shandong Agriculture University, Shandong Province, Taian City 271018, People's Republic of China. xcttaian2002@163.com
Chuantian
C
Xu
Weixing
W
Fan
Rong
R
Wei
Hongkun
H
Zhao
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002642:Chick Embryo; D006168:Guinea Pigs; D053127:Influenza A Virus, H9N2 Subtype; D009980:Influenza A virus / Q000737:chemistry / Q000235:genetics* / Q000302:isolation & purification; D008969:Molecular Sequence Data; D009976:Orthomyxoviridae Infections / Q000662:veterinary* / Q000821:virology; D010802:Phylogeny; D012367:RNA, Viral / Q000737:chemistry / Q000235:genetics; D051381:Rats; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000662:veterinary; D017422:Sequence Analysis, DNA; D012689:Sequence Homology, Nucleic Acid; D013552:Swine; D013553:Swine Diseases / Q000821:virology*
D012367:RNA, Viral