H9N2亚型猪流感病毒A/Swine/Shandong/1/02 分离株的基因序列分析

从有肺炎症状的病猪中分离到1株H9N2亚型猪流感病毒(SIV)A/Swine/Shndong/1/02,对其进行了全病毒基因序列分析.结果表明,该毒株8个基因片段的核苷酸序列均来自禽流感病毒(AIV),与我国目前家禽中流行的H9N2亚型AIV毒株具有很高的同源性,与A/Duck/Hong Kong/Y280/97(H9N2)的同源性为94.1%～98.9%,与A/Chicken/Beijing/1/94(H9N2)的同源性为94.5%～98.2%;推导的其血凝素(HA)裂解位点处的氨基酸序列为P-A-R-S-S-R,完全符合H9亚型AIV欧亚分支中的类A/Chicken/Beijing/1/94亚分支的特征;基因分析结果表明,该分离株的所有基因片段均来源于H9N2亚型AIV,它可直接感染猪,并导致发病,但它并未在猪体内发生重组.

Sequence analysis of genes of H9N2 subtype swine influenza virus isolate A/Swine/Shandong/1/02

Genetic characteristics of an influenza A(H9N2) virus,A/Swine/Shandong/1/02,isolated in Shandong Province from a pig with pneumonia,was analysed.The virus was proved to be genetically similar to the avian influenza A(H9N2) viruses currently circulating in Chinese poultry.Eight gene segments of A/Swine/Shandong/1/02(H9N2) were closely related to those of A/Duck/Hong Kong/Y280/97(H9N2) and A/Chicken/Beijing/1/94(H9N2),i.e.the identity rates of the gene segments between A/Swine/Shandong/1/02 and A/Duck/Hong Kong/Y280/97 or A/Chicken/Beijing/1/94 were 94.1%-98.9% or 94.5%-98.2%,respectively.The deduced amino acid sequence of HA cleavage site from A/Swine/Shandong/1/02 was P-A-R-S-S-R,which was accordance with characteristics of A/Chicken/Beijing/1/94 in the Eurasian branch of H9 subtype avian influenza virus(AIV).It was concluded that all the gene segments of A/Swine/Shandong/1/02 were from H9N2 AIV,and it could infect swine directly,and cause disease,but did not recombine in swine body.