人源H3N2亚型猪流感病毒A/Swine/Guangdong/1/2005的分离鉴定及全基因遗传演化分析

Isolation and identification of human influenza virus A/swine/Guangdong/1/05(H3N2)

2005年从广东某猪场采集疑似流感病猪的病料(气管和肺脏)样品共40份,通过MDCK细胞培养分离到6株A型流感病毒,经过血凝抑制和PCR扩增方法鉴定均为H3N2亚型。挑选其中一个代表株A/swine/Guangdong/1/05(H3N2)(SwGD1/05)进行全基因组测序并与GenBank中相关序列比较,结果发现SwGD1/05的8个基因分别与人流感病毒相关基因氨基酸同源性高达98.5%～99.4%;SwGD1/05的8个基因进化树中分别位于北美和欧洲人流感病毒进化谱系位置;由此推测SwGD1/05可能来源于北美或欧洲人源流感病毒株。这一结果为阐明猪作为流感病毒传播的中间宿主作用提供了的理论支持,本研究具有重要的人类公共卫生意义。

Six influenza virus strains were isolated from lung and trachea tissue of dead pigs with influenza-like clinical symptoms from South China in 2005. All isolates were identified as influenza A virus of H3N2 sub-type by PCR and HI method. The complete genome of A/Swine/Guangdong/1/05 （H3N2） （SwGD1/05） strain was sequenced and compared with those available in GenBank. The SwGD1/05 showed 98.5 %-99.4 % sequence homology and shared the same HA receptor sequences with the human influenza viruses. Phylogenetic analysis showed that SwGDl/05 was clustered in the same groups as the human influenza viruses. These results indicated that SwGDI/05 probably was originated from human influenza viruses of North America or Europe, with pigs as a intermedia-host of influenza viruses. These finding could have significanct implication in human public health.