大连市人肠道病毒71型的流行情况分析

Analysis of prevalence situation of human enterovirus 71 in Dalian

目的了解2009年-2011年大连地区人肠道病毒71型（EV71）流行情况；构建系统发生树和进行同源性分析，为今后EV71的防治及防控提供科学依据。方法将EV71阳性标本接种于人横纹肌肉瘤（RD）细胞，分离并提取病毒RNA，扩增出VP1基因片断，分析其核苷酸序列和氨基酸序列的同源性。结果2009年-2011年期间共检测533份样品，阳性率为62．48％。选取的9株EV71毒株均属于C4a亚型，其核苷酸之间的同源性为88．7％～99．9％；氨基酸之间的同源性为96．7％～100％。结论2009年-2011年大连地区手足口病的主要病原体为EV71，其基因型别为C4a亚型。重症来源的毒株，在VP1的第227位核苷酸发生了T→C的碱基置换，而轻症来源的毒株均未发生改变。

Objective To find out the EV71 epidemic from 2009 to 2011 in Dalian, to construct phylogenetic trees and analyze homology, so as to provide a scientific method for prevention, treatment and control of EV71 in the future. Methods EV71 positive samples were inoculated into RD cells, then the EV71 virus was separated after subculture to extract viral RNA and VP1 gene fragments were amplified, finally the homology of nueleotide sequence and amino acid sequence was analyzed. Results 1. From 2009 to 2011, five hundred and thirty -three samples were detected, the positive rate was 62.48%. 2. The 9 EV71 strains all belonged CAa subtypes, the nueleotide homology ranged from 88.7% to 99.9% , while it was 96.7% to 100% between amino acids. Conclusion 1. EV71 is the main pathogen and the genotype is C4a subtype for hand, foot and mouth disease in Dalian from 2009 to 2011.2. In the analysis of the strain＇s virulence, the strains from severe cases were found T→C base raplacement in VP1 region at the 227th nueleocide, while those from mild cases were not found changes.