手足口病重症病例特征分析及其病原型别分子鉴定

目的对2009年北京市西城区某哨点医院手足口病(hand foot and mouth disease,HFMD)重症病例特征进行初步分析,通过病原学分子分型鉴定,全面了解其病原构成,为重症HFMD的防控提供基础。方法采集重症HFMD患者咽拭子标本,提取病毒RNA。用实时荧光RT-PCR检测肠道病毒(EV)核酸,并对肠道病毒71型(EV71)和柯萨奇病毒A16型(CoxA16)进行分型检测;用肠道病毒VP4区分型引物进行半巢式RT-PCR(RT-nPCR),通过测序和序列分析对非EV71、非CoxA16型EV进行分型鉴定。结果 2009年4～12月,共采集HFMD重症标本35例,发病时间主要集中在6～8月,多为3岁以下婴幼儿。通过实时荧光RT-PCR检测,8例阴性,27例EV阳性,其中,13例EV71阳性,2例CoxA16阳性;12例非EV71、非CoxA16型EV经半巢式RT-nPCR检测,均扩增出目的片段,其中10例测序成功,并通过NCBI BLAST序列比对确定病毒型别:CoxA5和CoxA10各2例,CoxA2、CoxA4、CoxA6、CoxB5、Echoll、人鼻病毒各1例。结论重症手足口病发病高峰为6～8月,3岁以下婴幼儿为主要发病人群。2009年该哨点医院重症HFMD病原型别多样,以EV71为优势型别。

Analysis on the characteristics of severe hand foot and mouth disease cases and molecular typing of the causative agent

OBJECTIVE To analyze the characteristics of severe HFMD cases from one sentinel hospital of Beijing Xicheng district in 2009,and to investigate the etiological spectrum of severe HFMD by molecular typing of the enteroviruses(EV),to provide basis for the prevention and control of severe HFMD.METHODS The virus RNA was extracted from throat swabs collected from severe HFMD cases.Real-time RT-PCR was performed to detect EV nucleotide,and to identify EV71 and CoxA16;Non-EV71 non-CoxA16 EV were typed by nested RT-PCR with VP4 primers and sequence analysis.RESULTS A total of 35 sever HFMD specimens were collected from April to December of 2009.Sever cases mainly occurred from June to August.Most cases were under 3 years old.Tested by real-time RT-PCR,8 specimens were negative and 27 were positive for EV,out of which 13 were identified as EV71 and 2 as CoxA16.The target fragments were amplified by nested RT-PCR with VP4 primers from 12 specimens identified as non-EV71 non-CoxA16 EV.10 were sequenced successfully and their types were identified by NCBI sequence Blast:2 CoxA5,2CoxA10,1CoxA2,1CoxA4,1CoxA6,1CoxB5,1Echoll and 1human rhinovirus.CONCLUSION Severe HFMD cases peak from June to August,and most cases are under 3 years old.The EV types of severe HFMD cases from this sentinel hospital are diverse in 2009,with EV71 being the dominant type.