一株塞内卡病毒的分离与鉴定

Isolation and identification of a Seneca Valley virus strain

2018年11月,河南南阳地区某养殖场发生了猪水疱病,经实验室检测确诊为塞内卡病毒(SVV)感染。选择SVV检测阳性的临床样品,处理后接种PK-15细胞,经多次传代培养,成功分离到1株塞内卡病毒,命名为HeNNY-1/2018株,并在PK-15细胞上对该毒株进行了空斑纯化和生长曲线的绘制。为进一步研究其遗传进化特点,采用RT-PCR技术扩增了其全基因组序列,并分别构建了基于VP1基因和全基因组的系统进化树。结果表明,分离株HeNNY-1/2018在感染后第24小时病毒效价最高为107.6TCID50/m L。基因组核苷酸同源性分析显示,分离株HeNNY-1/2018与我国广西分离毒株GXHZH-1和美国毒株KS15-01呈现较高的核苷酸同源性,分别为98.0%和98.7%。进一步分子进化树分析显示,该毒株与2018年报道的广西地区的毒株处于较近的进化分支,而与我国早年间分离得到的其他毒株亲缘关系较远。本研究为河南地区塞内卡病毒流行状况提供了新的证据,也为下一步研究该病的诊断和防控提供了有力支撑。

One Seneca Valley virus(SVV)strain,named He NNY-1/2018,was isolated with the vesicular tissues collected from Nanyang region in 2018 through multiple passage culture and plaque purification in PK-15 cells.The growth curve of the isolate was further measured.To investigate the genetic characteristics of the isolate,the whole genome was sequenced and phylogenetic evolutionary was carried out based on the whole genome and VP1 gene with the MEGA6.0.The growth curve result showed that the maximum titer of He NNY-1/2018 strain was 107.6TCID50/m L at 24 h.Homological analysis showed that the genomic sequence of the isolate shared 98.0%and 98.7%nucleotide identities with GXHZH-1 and KS15-01 strains,respectively.Evolutionary tree analysis displayed that the He NNY-1/2018 was genetically close to the SVV strain reported in Guangxi Zhuang Autonomous Region in 2018 and far from the early prevalent strain in China.It indicated that the SVV strains in China had genetic differences during the epidemic.This study provides new evidence for the epidemic situation of SVV in Henan Province,central China,and provides strong support for the further study on the diagnosis,prevention and control of the disease.