Ma Jian-Min, Wei Hai-Yan, Yu He-Jun, Li Kun, Huang Xue-Yong
Xinxiang Center for Disease Control and Prevention, Xinxiang 453003, China.
Bing Du Xue Bao. 2012 Nov;28(6):675-80.
The study was performed to examine the enterovirus 71(EV71) VP1 genetic feature and the epidemiology of hand-foot-mouth disease (HFMD) in Xinxiang in 2011. Real-time RT-PCR was used for the detection of Pan-enterovirus, Coxsackievirus A 16(CA16) and EV71 from stool specimens of HFMD. The VP1 region was amplified from 10 EV71 positive samples and the products were sequenced. EV71 genotypes were characterized by homology and phylogenetic tree analyses. Additionally, epidemic data of Xinxiang HFMD in 2011 was analyzed. The results revealed that 73% of the specimens from severe cases were determined as EV71 positive, which was significantly higher than CA16-positive ones (19%) (P < 0.01). Ten EV71 strains isolated in Xinxiang belonged to C4a cluster of sub-genotype C4, with 2.8% nucleotide and 0.9% amino acid sequences divergence among them. At position 170 in VP1 gene, an alanine(A) was predominant in 9 isolates, while a valine(V) residue was observed in one isolate. Compared to the representative C4a strains which were closely related to Xinxiang isolates, the amino acid variations of the pre-dominant Xinxiang strains generally occurred at position 292, threonine --> alanine (T --> A). A total of 1118 HFMD cases were reported in Xinxiang in 2011, and 92% of them were younger than 3 years old; the incidence rate peaked in April and December, suggesting that it is very necessary to strengthen HFMD prevention and control even in cold weather.
本研究旨在检测2011年新乡地区手足口病（HFMD）肠道病毒71型（EV71）的VP1基因特征及流行病学情况。采用实时RT-PCR法从手足口病粪便标本中检测泛肠道病毒、柯萨奇病毒A16型（CA16）和EV71。从10份EV71阳性样本中扩增VP1区域并对产物进行测序。通过同源性分析和系统发育树分析对EV71基因型进行鉴定。此外，还分析了2011年新乡地区手足口病的流行数据。结果显示，重症病例标本中73%被判定为EV71阳性，显著高于CA16阳性病例（19%）（P<0.01）。新乡地区分离出的10株EV71毒株属于C4亚型的C4a簇，它们之间的核苷酸序列差异为2.8%，氨基酸序列差异为0.9%。在VP1基因的第170位，9株分离株中主要为丙氨酸（A），1株分离株中观察到缬氨酸（V）残基。与与新乡分离株密切相关的代表性C4a毒株相比，新乡优势毒株的氨基酸变异通常发生在第292位，苏氨酸→丙氨酸（T→A）。2011年新乡地区共报告手足口病病例1118例，其中92%为3岁以下儿童；发病率在4月和12月达到高峰，这表明即使在寒冷天气也非常有必要加强手足口病的防控。
