摘要目的 调查云南省昆明市登革热输入性病例分布状况及病原分子特征.方法 收集登革热病例资料,采集本病急性期病人血清标本,用ELISA法检测登革病毒(DENV) IgM抗体,RT-PCR法检测DENV核酸,核酸阳性者进行DENV-C/PreM区的基因核苷酸序列测定和分析,采用MEGA5软件的邻接法构建进化树.结果 2010-2013年在昆明市第三人民医院住院病人中采集到登革热临床诊断病例血清标本13份,经检测DENV-IgM抗体均为阳性,DENV核酸阳性2份.根据流行病学史、临床表现和实验室检测结果,这13例病人均被诊断为登革热.获得了两株病毒(YNH8和YNH12)的C/PreM区基因核苷酸序列,进化分析表明YNH8和YNH12株均为登革Ⅰ型病毒.其中YNH8株与南亚地区印度流行株进化关系最为接近,而YNH12株与泰国、缅甸、柬埔寨和越南等东南亚国家流行株具有较近亲缘关系.结论 昆明市登革热患者均为输入性病例.流行病学史和分子流行病学研究证实,YNH8和YNH12病例与印度和缅甸流行株具有较近亲缘关系.

abstractsObjective To investigate the distribution pattern and molecular characteristics of the pathogen of imported dengue fever cases from foreign into Kunming city of Yunnan province,China from 2010 to 2013.Methods The data of dengue fever cases in Kunming city were collected from 2010 to 2013.Serum samples from acute stage of these patients were collect to detect the nucleic acid of dengue virus by RT-PCR assay and sequencing.Neighbor-joining assay of MEGA 5 software was used to analyze the phylogenetic tree based on nucleotide sequence of C/PreM gene fragments of dengue virus using.Results A total of 13 sera were collected from acute stage of illness hospitalization at No.3 hospital of Kunming City.All samples were dengue virus IgM positive and two samples were dengue virus nucleic acid positive.The 13 cases were diagnosed for dengue fever according as medical history and laboratory assay.Two isolates (YNH8 and YNH12) of serun samples from dengue fever cases were identified as well as phylogenetic analysis was performed using nucleotide sequences of C/PreM gene fragments.Phylogenetic analysis showed that the two virus specimens belonged to dengue type Ⅰ virus (DENV-1) and could be clustered into one clade.However,the YNH8 was more close to the strains of DENV-1 from south Asia (India) and the YNH12 is more close to the strains of DENV-1 from southeast Asia countries (Myanmar,Thailand,Cambodia and Vietnam).Conclusions All patients of dengue fever in Kunming were imported cases.It is confirmed by case history and molecular epidemiology that YNH8 and YNH12 cases were close to the epidemic strain in Myanmar and India.