鸭源禽流感病毒的分离鉴定及特性研究

Isolation and identification of duck-derived avian influenza virus

从湖北某鸭场采集泄殖腔棉拭子 2 0份 ,通过传统的禽流感病毒分离方法即鸡胚尿囊腔接种法分离到 1株鸭源禽流感病毒 (AIV)。血清学试验表明 ,该病毒分离株为A型流感病毒 ,经血凝素亚型鉴定为H9型 ,与禽流感病毒H9亚型标准阳性血清的血凝抑制 (HI)价为 8log2 ,电镜负染拍照后 ,可清楚观察到典型的流感病毒粒子形态 ;致病性试验表明 ,该流感病毒对鸡表现为较低的致病力。研究表明 ,水禽 ,特别是鸭 ,正日益成为禽流感的高度易感动物 。

One H9 subtype strain of avian influenza virus (AIV) was isolated from 20 cloacal swabs of ducks in Wuhan.Agar-gel precipitin (AGP) antigen made from AIV isolate could react with serum against AIV.The hemagglution inhibition (HI) test indicated that this isolate belonged to H9 subtype of influenza A virus,and antiserum of H9 subtype was 8 log_2,which was negative in HI assays against Newcastle disease (ND) antiserum,Infectious bronchitis (IB) antiserum,Infectious bursal disease (IBD) antiserum,and Egg Drop Syndrome (EDS_(-76)) antiserum.Under electron micrograph,virions reveal the shape of spherical with an 80～120 nm diameter.The 50 percent embryo infectious dose (EID_(50)),intravenous pathogenicity index (IVPI) and intracerebral pathogenicity index (ICPI) were 10^(-6.37)/0.2 mL, 0.74 and 1.30.Results above show that the isolate is lowly pathogenicity.This implies that aquatic birds (especially ducks) have become the highly infectious animal and an important factor and medium for the perpetuation and transmission of avian influenza viruses.