2012— 2014 年上海市麻疹病毒学监测情况分析

摘要

本研究旨在通过对2012—2014年上海市麻疹病毒监测情况进行分析 ,研究上海市麻疹病毒流行株核蛋白(nucleoprotein ,NP)的基因特征 ,探索上海市不同传播链麻疹病毒的流行情况.用Vero/Slam细胞对采集的疑似麻疹病例咽拭子标本进行病毒分离 ,分离到的麻疹毒株用反转录-聚合酶链反应(reverse transcriptase-polymerase chain reaction ,RT-PCR)扩增NP羧基端450个核苷酸 ,并对扩增产物进行序列测定和基因亲缘性关系分析.2012—2014年上海市疾病预防控制中心共收到2 562份疑似麻疹病例咽拭子标本 ,分离到710株麻疹病毒流行株 ,病毒分离阳性率为27 .71% .分离到的麻疹病毒流行株中1株为D8基因型 ,8株为B3基因型 ,其余均为 H1a基因亚型.所有 H1a基因亚型分离株与世界卫生组织(World Health Organization ,WHO)参考株(GenBank No .AF045212)的核苷酸序列同源性为96 .0% ~98 .0% ,氨基酸序列同源性为92 .7% ~98 .0% .D8基因型分离株(SH12-239)与WHO参考株(GenBank No .AF280803)的核苷酸序列同源性为97 .8% ,氨基酸序列同源性为98 .6% .所有B3基因型分离株与WHO参考株(GenBank No . L46753 )的核苷酸序列同源性为96 .7% ~96 .9% ,氨基酸序列同源性为95 .3% .结果提示 ,2012—2014年上海市麻疹病毒流行株以H1a基因亚型为绝对优势亚型.上海市麻疹监测系统首次监测到 D8基因型和B3基因型麻疹病毒在中国内地的存在.%A 3-year retrospective study was performed based on virological surveillance data of measles virus in Shanghai from 2012 to 2014 .Vero/Slam cell line was chosen to isolate virus of throat swabs collected from suspected measles cases .The fragment of C-terminal of nucleoprotein was amplified by reverse transcriptase-polymerase chain reaction (RT-PCR) ,and the products were directly sequenced .The phylogenetic analysis of gene relationship was performed based on the 450 nucleotides of C-terminal of nucleoprotein .A total of 710 measles virus strains were isolated from 2 562 throat swab specimens (27 .71% ) .Almost all the isolates were subgenotype H1a ,except 1 genotype D8 and 8 genotype B3 .The identity of subgenotype H1a strains was 96 .0%-98 .0% for nucleotide sequence and 92 .7%-98 .0% for amino acid sequence respectively when compared with a World Health Organization (WHO ) representative reference strain (GenBank No . AF045212) .Whereas the nucleotide sequence identity and amino acid sequence identity between genotype D8 and WHO representative reference strain (GenBank No . AF280803 ) and between genotype B3 and WHO representative reference strain (GenBank No . L46753 ) were 97 .8% ,98 .6% and 96 .7%-96 .9% , 95 .3% ,respectively .The results suggest that subgenotype H1a measles virus is predominant in Shanghai from 2012 to 2014 .Imported genotype D8 and B3 measles virus strains are first found in Mainland China through Shanghai measles surveillance system .