通过病毒分离鉴定和基因检测首次发现虎流感

The First Finding of Tiger Influenza by Virus Isolation and Specific Gene Amplification

应用 F8 1 猫肾传代细胞 ,从高热、拒食和间有神经症状的死亡虎病料中分离获得 1株病毒 ,经形态学、理化学、生物学和血清学系统鉴定 ,证明为流感病毒。采用流感病毒核蛋白基因引物 ,对分离病毒及该虎病料进行 RT- PCR扩增和序列分析 ,结果从分离病毒和虎病料中均扩增出与理论值大小相符的 4 6 4 bp基因片段 ;其序列与 A、B、C 3型流感病毒相比较 ,同源性分别为 84 .9%、35 .0 %、2 4 .8%。由此说明 ,所分离病毒为 A型流感病毒 ,命名为 A/虎 /哈尔滨 (中国 ) / 0 1/ 2 0 0 2。用此分离病毒静脉接种于 3月龄家猫 3只 ,均出现与病虎相似的临床症状 ,其中 1只耐过 ,2只死亡。死亡猫剖检变化与死虎相似 ,主要呈现肺炎病变 ,并可从病料中回收到所接种病毒。以此分离病毒为 HA抗原 ,进行虎与猫血清的 HI抗体检测 ,结果康复虎血清比其病初血清、康复猫血清比其接种前血清 HI抗体均增高 4倍以上 ,表明该病毒具有致病性 ,是引起该虎与试验猫发病甚至死亡的病原。

An influenza virus-like virus isolate was obtained from the specimen of a tiger died of high fever,anorexia,and twitch.This virus was confirmed to be influenza virus by characteristics of its morphology,physiochemistry,biology and serology.Further analysis was performed by amplification of the specific nucleic acid of influenza virus nucleoprotein gene.A 464 bp cDNA fragment,being amplified from both the virus cell culture and the suspension of specimens,was compared with the published sequences of influenza virus type A,B,C with the homology of 84.9%,35.0%,24.8%,respectively,indicating that the virus is an influenza virus type A isolate.This virus has been designated as A/tiger/Harbin/01/2002.Three 3-month-old domestic cats were infected with the virus by intravenous inoculation.One of the infected cats survived the infection and the other two were seriously sick and eventually died of the infection.The ill cats presented similar clinical signs and pathological changes,characterized by pneumonia,to that of tigers.The inoculated virus could be reisolated from the lung.Specific antibodies against the virus were measured by hemaglutination inhibition test.The antibody titers of survived tigers and cats were over 4 times higher than that of the sick and uninfected ones,respectively,demonstrating that the virus is pathogenic and sometimes even fatal for tigers and cats.This is the first report that influenza virus types A exists in tigers.