繁殖障碍型H3亚型猪流感病毒的分离与鉴定

于广东惠州市某猪场采集流产死胎的肺组织、胎衣及鼻棉拭子,病料处理后经SPF鸡胚绒毛尿囊腔接种获得1株有血凝(HA)活性的病毒,通过AGP试验初步确定为猪流感流感病毒;但此病毒的血凝现象不能被抗H1亚型猪流感单因子血清、抗H5亚型猪流感单因子血清、抗H7亚型猪流感单因子血清、抗H9亚型猪流感单因子血清抑制,而能被抗H3亚型猪流感单因子血清抑制;通过H3亚型猪流感病毒RT-PCR分子生物学诊断,最终确定该病毒为H3亚型猪流感病毒.动物回归试验结果显示,攻毒小鼠出现精神萎靡、厌食、嗜睡、被毛松乱、呼吸较急促,攻毒后7 d采集小鼠血清进行检测,HI效价为3log2～4log2;剖检发现病毒性肺炎,且能从病料中再次分离到H3亚型猪流感病毒.

Isolation and identification of a porcine reproductive disease strain of H3 subtype swine influenza virus

A swine fever case broke out with serious reproductive symptoms in a swine farm from Huizhou of Guangdong province. The lung,placenta and swab samples from dead fetus were collected and mixed. A strain of virus was isolated by allantoic cavity inoculation with SPF chicken embryos, which was preliminarily classified as a strain of swine influenza virus with AGP test. The results demonstrated that the virus had haemagglutination activity detected by HA test, but could not be inhibited by positive sera against HI subtype,H5 subtype,H7 subtype and H9 subtype swine influenza virus individually,whereas the virus could be specially inhibited by positive sera against H3 subtype swine influenza virus ,and the positive result could be displayed by RT-PCR detection method developed in this lab. The results of animal regression test indicated that all inoculated mice had the respiratory symptoms and more typical pathology,which were dull,anorexia,drowsiness and wool chaos,HI antibodies of which were 3log2-4log2 by HI test on the seventh day post inoculation, and the result of the dissect investigation of which demonstrated that viral hepatitis happened.This strain of H3 subtype swine influenza virus could be isolated and identificated from inoculated miceagain.