2021年云南省环境污水中检出1株疫苗衍生脊髓灰质炎病毒  

A Strain of Vaccine-derived Poliovirus Isolated from Environmental Sewage in 2021 in Yunnan Province,China

作　　者：汤晶晶[1,2] 张杰 张筱碟[3] 李江嵘 祝双利 李晓嫘[4] 严冬梅[4] 李凯 丁峥嵘[1,2] TANG Jingjing;ZHANG Jie;ZHANG Xiaodie;LI Jiangrong;ZHU Shuang;LI Xiaolei;YAN Dongmei;LI Kai;DING Zhengrong(Yunnan Provincial Center for Disease Control and Prevention,Kunming 650022,China;Yunnan Center of Enterovirus Research,Kunming 650022,China;Kunming Medical University,Kunming 650022,China;Chinese Center for Disease Control and Prevention,Beijing102206,China)

机构地区：[1]云南省疾病预防控制中心,昆明650022 [2]云南省肠道病毒研究中心,昆明650022 [3]昆明医科大学,昆明650022 [4]中国疾病预防控制中心,北京102206

出　　处：《病毒学报》2022年第6期1289-1296,共8页Chinese Journal of Virology

摘　　要：为了解云南省污水中脊髓灰质炎(脊灰)病毒(Poliovirus,PV)的变异特征,为维持无脊灰工作提供依据,本研究于2021年1-12月在昭通市开展了环境污水监测研究。每月采集某污水处理厂水样标本800mL,采用阴离子膜吸附洗脱法对样品进行浓缩处理,进行PV分离。PV分离物进行实时荧光定量RT-PCR型内鉴定和VP1区核苷酸序列分析,并对发现的一株Ⅲ型疫苗衍生脊髓灰质炎病毒(Vaccine derived poliovirus,VDPV)进行全基因组序列测定与生物学特征分析。昭通市2021年的12份水样中,3份(3/12,25%)分离到10株PV,其中1株为Ⅲ型VDPV,与Ⅲ型Sabin株相比,VP1编码区存在10个变异;另外9株为疫苗相关株。该VDPV基因组全长7432 nt,编码2207个氨基酸,与SabinⅢ疫苗株全基因组核苷酸和氨基酸序列的相似性分别为99.2%和99.5%。系统进化分析显示,昭通VDPV株在进化树中处独立分支,同其他国家及地区的Ⅲ型VDPV序列无明显相关性。关键位点分析显示该VDPV毒株有2个减毒位点(nt 472、nt 2493)发生了回复突变。温度敏感性实验表明该Ⅲ型VDPV分离物的温度敏感性有所降低。本研究结果证明了PV的环境监测具有较高的敏感性,是急性弛缓性麻痹(Acute flaccid paralysis,AFP)病例监测的有效补充。在我国边境省份开展环境监测对于防控VDPV的潜在传播甚至脊灰野病毒的输入及将防控关口前移具有重要的意义。We wished to understand the variation characteristics of the poliovirus(PV)from environmental sewage in Yunnan Province(China)and provide evidence for maintaining polio-free status.Zhaotong was selected as a monitoring point.A sample of environmental sewage(800mL)was collected each month from January to December 2021 for concentration,PV isolation,intra-typic differentiation and sequence analyses of the VP1 region of PV isolates.A type-Ⅲvaccine-derived poliovirus(VDPV)strain was identified,and the complete genome sequences of the isolate were determined and analyzed.Twelve samples of environmental sewage were collected,with 10 PV strains isolated from three samples.The VDPV strain had 10 nucleotide mutations in the VP1 region upon comparison with the type-ⅢSabin strain.The others were Sabin-like strains.Sequencing revealed that the complete genome length of the type-ⅢVDPV isolate was 7,432 nucleotides,and encoded a potential polyprotein precursor of 2,207 amino acids.Similarities in the sequences of nucleotides and amino acids of the VDPV strain were 99.2%and 99.5%,respectively,as compared with the Sabin strains.Phylogenetic analyses showed that the Zhaotong VDPV strain was in an independent branch of the tree,and was not homologous with previous type-ⅢVDPV strains from other countries and regions.Nucleotide substitutions were observed at two important attenuation sites(nt 472 and nt 2,493).Temperature-sensitive experiments showed that the temperature sensitivity of the Zhaotong VDPV strain had decreased.Isolation of a type-ⅢVDPV strain demonstrated the sensitivity of environmental surveillance,which was an effective supplement to surveillance of cases of acute flaccid paralysis.Such surveillance is very important for predicting and warning of VDPVs.Establishment of environmental surveillance in the border provinces in China is very important.

关 键 词：环境监测 疫苗衍生脊髓灰质炎病毒 基因特征 序列测定和分析 

分 类 号：R373.2[医药卫生—病原生物学]