论文部分内容阅读
目的研究广东省2009年肠道病毒71型的基因特征及流行趋势。方法收集广东省各地市手足口病病例的粪便、肛拭子、咽拭子、疱疹液和脑脊液等肠道病毒71型核酸阳性标本进行病毒分离及鉴定,选取粤东、粤西、粤北、珠三角4个地区16例病例的16株代表株进行vp1区全序列片段扩增,并运用DNASTAR 6和MEGA 4.02软件,将16株代表株的vp1全序列与从GenBank中下载的肠道病毒71型各代表基因型(亚型)进行同源性分析,并构建系统发生树。结果所选16株代表株经vp1区全序列片段扩增,扩增片段长度为1 042 bp,经测序和拼接后获得的序列片段长度为891 bp。16株代表株与肠道病毒71型A型和B型的亲缘性较远,核苷酸和氨基酸的同源性分别在81.5%～84.6%和94.3%～97.0%之间;与C型的亲缘性较近,核苷酸和氨基酸的同源性分别在87.4%～93.5%和97.6%～99.3%之间,其中与C4亚型的亲缘性最近,核苷酸和氨基酸的同源性分别在92.5%～93.5%和98.3%～99.3%之间。构建系统发生树表明,该16株代表株与国内外C4亚型处于同一簇,属肠道病毒71型的C4基因亚型C4 a群。结论广东省2009年肠道病毒71型的流行株属于C4亚型,为C4亚型的C4 a群,且全省范围内均有流行。
Objective To study the genetic characteristics and epidemiological characteristics of enterovirus 71 in Guangdong province in 2009. Methods The virus was isolated and identified from enterovirus 71 positive samples such as feces, anal swabs, throat swabs, herpes fluid and cerebrospinal fluid (CSF) in hand, foot and mouth disease cases from different cities in Guangdong Province. 16 representative strains of 16 cases in 4 regions of the Pearl River Delta were amplified by full-length fragment of vp1 region. The complete vp1 sequence of 16 representative strains was compared with that of enterovirus 71 downloaded from GenBank by DNASTAR 6 and MEGA 4.02 software Homology analysis of all representative genotypes (subtypes) and construction of phylogenetic tree. Results The selected 16 representative strains were amplified by the full-length fragment of vp1 region. The amplified fragment was 1 042 bp in length. The length of the amplified fragment was 891 bp after sequencing and splicing. The 16 representative strains were more distantly related to enterovirus type A and type B than type A and type B, the nucleotide and amino acid homologies were between 81.5% -84.6% and 94.3% -97.0%, respectively. The homology of nucleotides and amino acids were between 87.4% -93.5% and 97.6% -99.3%, respectively. Among them, the homology with the C4 subtype was the closest, and the nucleotide and amino acid homologies were respectively Between 92.5% -93.5% and 98.3% -99.3%. The phylogenetic tree indicated that the 16 representative strains were in the same cluster with the C4 subtypes at home and abroad, belonging to C4 subgroup C4 a of enterovirus 71. Conclusion The epidemic strains of enterovirus 71 in Guangdong Province in 2009 belonged to C4 subtype and C4 subtype C4 a group, all of which were endemic in the whole province.