基于血清学和分子流行病学证实的麻疹爆发研究

Study on Measles Outbreaks Based on the Confirmation of Serological and Molecular Epidemiology

目的分析5起麻疹爆发的调查结果,确证5起麻疹爆发间分子水平的关联,探讨麻疹爆发规模与血清学诊断时限、调查接种率水平及应急免疫完成情况等之间的可能关联,为修订控制麻疹措施提供数据。方法利用Excel2007对来自麻疹监测系统的5起爆发的资料及现场调查的资料进行统计整理,对5起麻疹爆发的病毒分离株代表株,用逆转录-聚合酶链反应扩增核蛋白(Nucleoprotein,NP)基因片段后测序,分析其NP基因亲缘关系及其核苷酸同源性。结果从血清学和分子生物学角度证实了5起麻疹爆发,确证了一个麻疹病毒传播链循环传播致5起大小不同的麻疹爆发。如果血清学诊断和应急免疫能在短时间内完成,那么调查接种率和应急免疫接种率越高,其爆发规模越小,爆发持续时间越短。结论控制麻疹爆发需要维持高水平的常规免疫接种率;当出现麻疹爆发时需提供早期快速的实验室诊断,并依据爆发调查结果科学选择合适目标人群,并快速完成高水平的应急免疫接种。

Objective To analyze the investigation results of 5 measles outbreaks, confirm the molecular relationship among the 5 outbreaks, to discuss the possible relationship between the scale of measles outbreaks and the time limit of serological diagnosis, and the relationship between investigated immunization rate and completed status of emergent immunization, so as to provide the data for measles control. Methods To analyze the data collected of the 5 outbreaks from measles surveillance system by software of Excel 2007. All measles representative strains from 5 outbreaks were detected the N gene by the reverse transeription-polymerase chain reaction （RT-PCR） and then sequenced for the RT-PCR products. To analyze the gene phylogenetic relationship and the variation of the predicted amino acid. Results 5 measles outbreaks were confirmed by both serology and molecular biology, and also confirmed the 5 outbreaks resulted from one strain transmission link. If the serological diagnosis and emergent immunization activity were finished within short time, the higher the investigation immunization rate and the emergent immunization rate are, the smaller the outbreaks scale will be, the shorter outbreak duration will be too. Conclusions To eradicate and control measles outbreaks need to maintain high level of routine immunization rate. It is needed to provide early rapid lab. diagnosis when measles outbreaks and to choose suitable target population to finish high emergent immunization rate rapidly.