2009年夏季174例手足口病患儿病原分析

A pathogen analysis within 174 cases of Hand-foot-mouth disease in the summer of 2009

目的分析本院2009年夏季手足口病患儿病原及其血清型特征，为临床早期诊断和疾病防控提供实验依据。方法2009年4—9月，首都儿科研究所附属儿童医院门诊就诊的174例手足口病患儿咽拭子和疱疹液，实时荧光RT—PCR方法检测肠道病毒通用型（EV）、柯萨奇A16型（CA16）、肠道病毒71型（EV71）。131例患儿双份血清，同时检测CA16、EV71IgM抗体。CA16和EV71阳性标本扩增VP1区基因片段后测序，进行同源性和系统进化分析。结果（1）EV、CA16、EV71阳性例数分别为167、112、46；阳性率为96．O％、64．4％、26．4％，CA16：EV71为2．43：1。（2）首诊血清CA16和EV71IgM阳性例数为51、25，阳性率为38．9％、19．1％，复诊阳性例数为98、32，阳性率为74．8％、24．4％。（3）CA16VP1区核苷酸同源性为88．7％-98．5％，EV71VP1区核苷酸同源性为94．9％-99．7％，与c4亚型参比序列核苷酸同源性92．1％～95．3％。结论2009年夏季本院手足口病患儿病原以CA16、EV71为主，EV71阳性率较之前报道有较大幅度升高。EV71病毒株以c4亚型为主。实时RT-PCR法较血清学检测特异性IgM抗体更适于疾病早期诊断。

Objective To analyze the pathogen and characteristics of the serum types of enterovirus of hand-foot-and-mouth disease （I-IFMD） in the summer, 2009. Methods Both throat swab and herpes fluids were taken respectively from 174 children with I-IFMD in the outpatient infection during April to September, 2009. Anti-Cox A16 and anti-EV71 IgMs in the serum were detected with ELISA. And RNA were extracted from each sample followed with real-time fluorescence quantitative RT-PCR kits with three reagents： universal enterovirus primer, Coxsackievirus A16 （CA16） primer and enterovirus 71 （EVT1） primer. Parts of positive samples were sequenced and analyzed. Results （1） EV genes were detected from 167 cases, of which , 112 cases were positive for CA16 and 46 were positive for EV71. CA16：EV71 was 2.43： 1. （2）There were 51 cases with CA16 IgM positive and 25 cases with EV71 IgM positive in the early collected sera, and in the later samples, 98 cases with CA16 IgM positive and 32 cases with EV71 IgM positive. （3）The nucleotide homologies were 88.7%-98.5% of VP1 gene among CA16. The nucleotide homologies were 94.9% -99.7% of VP1 gene among EV71, and were 92. 1% -95.3% with C4 subtype. Conclusion The mainly pathogen causing HFMD in children in the summer, 2009 were CA16 and EV71. EVT1 infection, mainly C4 subtype, was highly elevated according to the earlier reported. Real-time RT- PCR is more appropriate than the serological test.