病毒学报

为了解山东省2011年分离的1株脊髓灰质炎(脊灰)疫苗高变异株的基因特征,并对该病例接触者标本进行病原学鉴定及分析。本研究对采集的2份病例及40份接触者粪便标本进行病毒分离,对脊灰病毒进行全基因组序列测定和分析,对非脊灰肠道病毒进行VP1区序列测定,并将分离率较高的柯萨奇病毒(Coxsackievirus,CV)B1和CV-B3与国内外其他地区分离株进行VP1区同源性及系统进化树分析。其中病例标本中分离到1株脊灰病毒(P1/11186),1株CV-A4和1株CV-A8;接触者标本中分离到1株CV-A2、10株CV-B1、5株CV-B3和埃可病毒(Echovirus,E)3型、12型、14型各1株,提示当地可能存在肠道病毒流行,应加强监测。P1/11186为Ⅰ型脊灰疫苗病毒,在2A及3A区分别与Ⅱ型和Ⅲ型脊灰病毒发生重组,与相应的疫苗株相比全基因组共有25个核苷酸、9个氨基酸发生变异,其中VP1区8个核苷酸、5个氨基酸发生突变。CV-B1和CV-B3的同源性分析显示10株CVB1之间核苷酸同源性为97.0%~100%,氨基酸同源性为98.9%~100%;5株CV-B3之间核苷酸与氨基酸同源性分别为92.6%~100%与99.2%~100%。CV-B1与CV-B3VP1完整编码区进化树分析显示,山东分离株与国内其他省份分离株亲缘关系较近,位于同一基因簇,与世界其他地区分离株位于不同分支。

To analyze the genetic characteristics of a polio-I highly variant vaccine recombinant virus in Shandong Province(China)in 2011 and to identify isolates from healthy contacts,two stool specimens from one patient with acute flaccid paralysis(AFP)and 40 stool specimens from his contacts were collected for virus isolation.The complete genome of poliovirus and VP1 coding region of the non-polio enterovirus were sequenced.Homologous comparison and phylogenetic analyses based on VP1 sequences were undertaken among coxsackievirus(CV)B1,CV-B3 isolates,and those in GenBank.One poliovirus(P1/11186),CV-A4 and CV-A8 were isolated from the AFP patient;one CV-A2,Echovirus 3(E-3),E-12 and E-14,ten CV-B1,and five CV-B3 strains were isolated from his contacts.These results led us to believe that there may be a human enterovirus epidemic in this area,and that surveillance must be enhanced.P1/11186 was a type-1vaccine-related poliovirus;it combined with type-2and type-3polioviruses in 2Aand 3Aregions,respectively.There were 25 nucleotide mutations with 9amino-acid alterations in the entire genome.There were 8nucleotide mutations with 5amino-acid alterations in the VP1 region compared with the corresponding Sabin strains.Homology analyses suggested that the ten CV-B1 isolates had 97.0%-100% nucleotide and 98.9%-100% amino-acid identities with each other,as well as 92.6%-100% nucleotide and 99.2%-100% amino-acid identities among the five CV-B3 isolates.Phylogenetic analyses on the complete sequences of VP1 among CV-B1 and CV-B3 isolates showed that Shandong strains,together with strains from other provinces in China,had a close relationship and belonged to the same group.