2010年浙江省输入性登革2型病毒分子特征研究

目的:为确证2010年浙江省输入性疑似登革热病例病因,分析病原的分子特征并进行溯源。方法:对患者血清标本分别检测登革IgM抗体、病毒核酸和病毒分离。对分离株E和NS1基因测序,并进行同源性和进化分析。结果:从血清中检测到登革IgM抗体和登革2型核酸,并分离到登革2型病毒株(ZJ/02/10);浙江登革2型分离株与标准株NGC在E基因的核苷酸(nt)和氨基酸(aa)同源性分别为94.7%和97.6%,而与登革1、3、4型的nt同源性分别为65.3%、64.3%和65.9%。ZJ/02/10株与菲律宾PHI/St68/00株E基因nt和aa同源性最高,进化树显示二者亲缘关系最近。NS1基因进化树结果与E基因相似。结论:从血清学、病原学和分子特征均证实输入性疑似登革病例由登革2型病毒引起,该毒株最有可能来源于菲律宾。

Study on the molecular characteristics of dengue vius type 2 isolated from imported patient in Zhejiang province in 2010

Objective:To confirm the aetiology of an imported dengue fever case reported in Zhejiang province in 2010,and to analyze the molecular characteristics and trace of the pathogen.Methods: IgM antibody and nucleic acid of dengue virus were detected,and the virus was isolated from the serum sample collected from the suspected dengue fever case.E and NS1 genes of the isolated strain were sequenced,and their phylogenetic and homology trees were constructed.Results: IgM antibody and RNA of type 2 dengue virus were detected in the serum sample,and type 2 dengue virus named ZJ/02/10 was isolated from the serum sample.The homology of nucleotide(nt) and amino acid(aa) in E gene of ZJ/02/10 and standard type 2 dengue virus NGC strain were 94.7% and 97.6% respectively,but the homology of nt with dengue virus type 1,3,and 4 were 65.3%,64.3% and 65.9%.The ZJ/02/10 strains had the highest similarity with the strain(PHI/St68/00)in both nt and aa of E gene,indicating the closet relation on the phylogenetic tree of E gene.The phylogenetic tree of the NS1 genes was similar to that of E gene.Conclusion: All of the serological,pathological and molecular features demonstrated that the suspected imported case of dengue fever was caused by type 2 dengue virus which was most likely from Philippines.