摘要
目的分析河北省邯郸市两起麻疹家庭聚集性疫情的特征。方法采集患者血清标本和急性期咽拭子标本,分别进行麻疹IgM和Ig G抗体亲和力检测及病毒分离培养。提取分离的麻疹病毒RNA,采用RT-PCR法扩增麻疹病毒核蛋白(N)基因羧基末端450个核苷酸序列,用Mega 6.0软件和麻疹病毒标准株参考序列构建亲缘性关系树,确定分离株的基因型。结果两起疫情共确诊麻疹病例5例,每起均出现了二代病例。其中1例病例有两剂次麻疹类疫苗免疫史,麻疹Ig G相对亲和力指数(relative avidity index,RAI)<40%,属于原发性免疫失败。5例病例咽拭子标本经基因亲缘性关系分析,均为D8基因型麻疹病毒;5株病毒序列与D8基因型参考株(D8-Manchester.UNK/30.94)的核苷酸和氨基酸同源性较高,分别为98.4%~98.6%和97.3%,与中国本土H1基因型参考株核苷酸和氨基酸同源性较低,分别为92.8%~93.1%和93.3%,与同时期流行于东南亚地区的D8基因型核苷酸和氨基酸同源性均为100.0%。结论引起两起家庭聚集性疫情的麻疹病毒为D8基因型,经直接或间接接触传播。积极开展应急接种能够避免更广泛的传播。
Objective To analyze the characteristics of two family clusters of measles virus infection in Handan city,Hebei province.Methods The serum and throat swab samples in acute phase were collected for measles IgM detection and IgG avidity determination,and for virus isolation respectively.RNA of the isolated measles viruses were then extracted and the 450bp of N gene were amplified by RT-PCR.The sequences of isolated viruses and reference strains were analyzed by Mega 6.0 for phylogenic trees construction and genotyping.Results A total of 5measles cases were confirmed.The secondary infection cases occurred in each family.One of the confirmed cases had two doses of measles vaccine immunization history.However,the IgG antibody affinity test for measles showed his IgG relative avidity index(RAI)was less than 40%,suggested primary immunization failure.Through genetic relationship analysis,5 throat swab specimens were all D8 genotype measles viruses.The nucleotide and amino acid among these 5 measles viruses and the WHO reference strain of D8 genotype were high homologous,that were 98.4%-98.6%and 97.3%,respectively.Compared with the prevalent strains of H1 genotype in China,the nucleotide and amino acid identity were relatively low in homology,that were 92.8%-93.1%and 93.3%,respectively.The homology of nucleotide and amino acid were 100.0%identical to the D8 genotype measles virus prevalent in Southeast Asia at the same period.Conclusion The measles virus caused two family clusters were D8 genotype.These viruses had strong transmission ability and can be transmitted through direct or indirect contact.Through active emergency vaccination,a wider range of transmission can be avoided.
作者
杜慧
丛艳丽
王伟
张敬坡
郭玉
张振国
DU Hui;CONG Yan-li;WANG Wei;ZHANG Jing-po;GUO Yu;ZHANG Zhen-guo(Institute for Immunization Planning and Management,Hebei Provincial Center for Disease Control and Prevention,Shijiazhuang,Hebei 050021,China;不详)
出处
《中国国境卫生检疫杂志》
CAS
2022年第3期235-239,共5页
Chinese Journal of Frontier Health and Quarantine
