鸭坦布苏病毒山东流行株的分离鉴定及其基因组序列分析

Isolation and Identification of Shandong Strain of Duck Tembusu Virus

为了解山东省鸭坦布苏病毒(duck tembusu virus,DTMUV)的流行与变异情况,对2018年下半年至2019年上半年泰安、济宁和淄博等地送检的临床病鸭样品进行了DTMUV病原学检测,并对阳性病料进行病毒分离鉴定及分离株的全基因组序列分析。结果显示:从102份样品中,共检测到8份DTMUV阳性,阳性率检出率为7.8%,从阳性病料中分离到3株DTMUV分离株;3个分离株基因全长均为10993 bp,彼此间的氨基酸同源性为99.2%~99.3%,与24个参考毒株的同源性为95.8%~99.9%,均属于中国株I型;与参考毒株相比,分离株的核衣壳蛋白C、囊膜蛋白E和非结构蛋白NS1的同源性相对较低,分别为86.1%~99.2%,95.0%~99.4%和92.3%~99.7%,同时存在数量不等的氨基酸突变位点,但关键的蛋白结构和潜在的糖基化位点无差异。结果表明,DTMUV在山东部分地区仍有流行,但流行毒株基因结构及致病特性与经典毒株相比无明显变化,但应持续关注和深入研究。

In order to identify the prevalence status and variation of duck Tembusu virus(DTMUV)in Shandong Province,the clinical samples delivered from Tai'an,Jining and Zibo during the second half of 2018 to the first half of 2019 were detected for DTMUV,and virus isolation and identification were carried out towards the positive samples,then the whole genome sequences of the isolates were analyzed.The results showed that 8 out of 102 samples were positive,with the detection rate of 7.8%,from which,3 strains of DTMUV were isolated;the full lengths of all the three strains were all 10993 bp,the amino acid homology of they ranged from 99.2%to 99.3%,and the homology between the isolates and 24 reference strains ranged from 95.8%to 99.9%,all the isolates fell into Chinese strain I;compared to the reference strains,the homologies of nucleocapsid protein C,envelope protein E and nonstructural protein NS1 of the isolates were lower,which were 86.1%to 99.2%,95%to 99.4%and 92.3%to 99.7%,respectively,and with different number of amino acid mutation sites,but major protein structures and potential glycosylation sites had no difference.It was concluded that DTMUV was still prevalent in some regions in Shandong Province,which should be further concerned and studied,although its genetic structure and pathogenicity remained unchanged compared to the classical strains.