支气管炎型H9亚型禽流感病毒的分离与鉴定

广东省某鸡场发生一起以严重呼吸困难、急性死亡为特征的病例,5000只鸡在1周内连续死亡400多只。通过病理剖检,几乎所有病死鸡支气管都充满干酪样物质,导致支气管严重阻塞,气管及支气管黏膜严重出血。采集病死鸡的肝脏、脾、肺和气管干酪样物质,病料经处理后通过SPF鸡胚绒毛尿囊膜接种获得一株病毒。通过琼脂凝胶免疫扩散(AGP)试验,该病毒能与禽流感标准阳性血清形成明显沉淀线,初步确定该病毒为禽流感病毒;通过血凝HA试验,该病毒能够凝集鸡红细胞,但此血凝现象不能被抗NDV血清、抗EDSV-76血清、抗H 5亚型流感单因子血清、抗H 7亚型流感单因子血清所抑制,而能被抗H 9亚型禽流感单因子血清所抑制,以及通过H 9亚型流感病毒的RT-PCR分子生物学诊断方法,最终确诊该病毒为H 9亚型禽流感病毒。动物回归试验,攻毒鸡表现与临床发病鸡一致的症状及典型病理变化,患鸡支气管被干酷样物严重阻塞,气管、支气管黏膜较严重出血,通过病料的病毒分离与鉴定,能再次分离到该病毒。

Isolation and Identification of a Bronchitis Strain of H9 Subtype Avian Influenza Virus

A sudden death case was broken out with serious respiratory symptoms in a chicken farm of Guangdong province,which about 400 of 5000 fowls died in only one week.The bronchiolus of almost all ill or dead chickens were full of cheese substances and obstructed,and serious hemorrhage of trachea and bronchial mucous membrane could also be seen.The liver,spleen,lung and cheese substances from dead chickens were collected and mixed,a strain of virus was isolated by allantoic cavity inoculation with SPF chicken embryos,and been preliminarily classified as a strain of avian influenza virus.The results demonstrated that the virus had haemagglutination activity detected by HA test,but could not be in hibited by positive sera against NDV,EDSV-76 as well as H5 subtype and H7 subtype AIV,whereas the virus could be specially inhibited by positive sera against H9 subtype AIV,and the positive result could be displayed by RT-PCR detection method of H9 subtype AIV developed in this lab.The results of animal regression test indicated that all inoculated chickens had the same symptoms and typical pathology as that of ill or dead chickens above,which the bronchiolus of almost all ill or dead chickens were full of cheese substances and obstructed,the mucous membrane of trachea and bronchial occurred more serious hemorrhage.This strain of H9 subtype AIV could be isolated and identificated from inoculated chicken again.