上海地区2005年麻疹流行株基因特性分析

目的了解2005年上海部分地区麻疹暴发流行株的基因型别和特性,加强麻疹病毒学监测。方法采集暴发麻疹患者咽拭子标本分离病毒,通过RT-PCR扩增麻疹病毒N基因C末端450 bp核苷酸并进行序列测定,与GenBank中麻疹病毒各基因型参考株及国内其他地区的麻疹分离株进行基因比较。结果从10例麻疹患者的咽拭子标本中共分离麻疹病毒4株,均属H基因组H1基因型,型内变异0.7%-1.3%。与H1型代表株China93-7的基因同源性为98%-98.2%;与H2基因型代表株China94-1的基因差异为6.4%-6.9%。与A型代表株Edmonston的基因差异为6.7%- 6.9%;与中国麻疹疫苗株Shanghai191的基因差异为7.6%-8.0%,与国内其他地区麻疹流行株基因差异为0.2%-3.7%。结论2005年上海部分地区麻疹暴发是由H1基因型病毒引起,为中国本土流行株。

Sequence analysis on measles viruses isolated in Shanghai in 2005

Objective To ascertain the genetic characterization and genotype of measles viruses isolated in Shanghai region, in 2005. Methods Measles virus was isolated from throat swab specimens collected from suspected measles cases and 450 bp fragment of C terminus of nucleprotein (N) gene was amplified by RT-PCR. Sequence analysis was conducted to ascertain the genotype and to compare the difference of nucleotide with other measles virus strain published in GenBank. Results 4 measles viruses were isolated from 10 throat swab specimens, and the sequence analysis indicated that they belonged to H1 genotype. The homogeneity of 450 nucleotides in the C terminal of the N gene was at 98%-98.2% as compared to H1 genotype (China93-7) .They differed from genotype H2 (China94-1) at 6.4%-6.9% and from genotype A (Edmonston) at 6.7%-6.9%, from measles vaccine (Shanghai191) at 7.6%-8.0%. They differed from the other measles viral strain isolated in China in 1993-2005 at 0.2%-3.7%. The variation within 4 isolated measles viruses was at 0.7%-1.3%. Conclusion It was H1 genotype measles viruses, which are the native viruses in China that led to the outbreak of measles in Shanghai, in 2005.