宁波地区2004～2008年麻疹野病毒分离株基因特征分析

Genetic Characteristic of Wild-type Measles Viruses Isolated in Ningbo From 2004 to 2008

目的了解宁波地区流行的麻疹野病毒基因型别和特性。方法对2004～2008年宁波地区分离到的麻疹野病毒,采用逆转录-聚合酶链反应扩增麻疹病毒核蛋白基因碳末端456个核苷酸并进行序列测定,与基因库中麻疹病毒各基因型参考株比较并分析毒株变异情况。结果2004～2008年共分离到麻疹病毒22株,均属H1基因型,与H1型参考株China93-7的核苷酸同源性为97.1%～98.5%,与中国疫苗株沪191的核苷酸/氨基酸差异为8.0%～9.5%/9.8%～14.5%;其中16株与H1a参考株China93-2的核苷酸同源性为98.2%～99.6%,属于H1a亚型;6株与H1b参考株China94-7的核苷酸同源性为98.5%～98.9%,属于H1b亚型。结论宁波地区2004～2008年流行的麻疹病毒均为H1基因型,且以H1a亚型为主,亦存在H1b亚型。

Objective To investigate the genetic characterizations and genotypes of measles viruses that was prevalent in Ningbo city. Methods Measles viruses were isolated from throat swab specimens of suspected measles cases from 2004 to 2008 and 456 bp fragments of C terminus of nucleprotein （N） gene were amplified by RT-PCR. Sequence analysis was conducted of all 22 virus strains while compared with other measles virus strain which published in GenBank. Results All of the 22 measles isolates belonged to genotype H1. The homogeneities of 456 bp fragments of C terminus of nucleprotein （N） gene were as high as 97.1%～98.5%,98.2%～99.6% and 98.5%～98.9% respectively. The nucleotide （amino acids） variability was 8.0%～9.5% （9.8%～14.5%） compared to S191. Conclusion Genotype H1 measles virus circulated in Ningbo,China from 2004 to 2008. H1a was the predominant epidemic strain,H1b strain was existed as well.