Ma Jiang-tao, Chen Hui, Ma Xue-ming, Guan Guang-yu, Hao Qiong, Wen Qiu-fang, Sun Xiao-qiang, Yang Dong-zhi, Wu Zhong-lan, Zhan Jun, Tan Xiao-juan, Xu Wen-bo
Ningxia Hui Autonomous Region Center for Disease Control and Prevention, Yinchuan 750004, China.
Zhonghua Shi Yan He Lin Chuang Bing Du Xue Za Zhi. 2010 Oct;24(5):324-6.
To analyze the genetic characteristics of EV71 strains isolated from HFMD cases in Ningxia Hui Autonomous Region in 2009.
In 2009, totally 385 specimens from 344 HFMD cases were collected from Ningxia. Enterovirus isolation was performed in RD cell line from all the specimens. EV71 isolates were identified by specific RT-PCR from the positive cultures, and sequences of complete EV71 VP1 encoding region were determined for farther analyses.
Totally from 126 EV strains isolated in this study, 58 EV71 strains (46%) were identified. And complete VP1 sequences of 46 EV71 strains were determined, and genetic analyses were performed. It was showed that the nucleotide identity of 46 Ningxia strains with the representatives of A and B genotypes were 81.7%-82.8% and 83.1%-85.2%, and the amino acid identity were 93.9%-95.9% and 96. 2%-97.9% respectively. The nucleotide identity of NingXia EV71 isolates with representatives of subgenotype C1, C2, C3, C4a, C4b, and C5 were 88.3%-90.6% (97.9%-99.6%), 88.3%-90.1% (97.9%-99.3%), 87.8%-89.0% (97.6%-98.9%), 94.2%-98.9% (97.9%-100%), 91.8%-94.1% (98.6%-99.6%), and 86.7%-89.1% (97.9%-98.9%). Phylogenetic tree analysis revealed that 46 stains were clustered with reference stains of subgenotype C4 and the Ningxia EV71 isolates were belonged to subgenotype C4a.
EV71 of subgenotype C4a had spread widely in Ningxia in 2009, which was absolutely predominant type in Ningxia in 2009 and also as the predominant type in China mainland since 2005.
分析2009年宁夏回族自治区手足口病病例中分离出的肠道病毒71型（EV71）毒株的基因特征。
2009年，从宁夏344例手足口病病例中采集了385份标本。所有标本均在RD细胞系中进行肠道病毒分离。从阳性培养物中通过特异性逆转录-聚合酶链反应（RT-PCR）鉴定EV71分离株，并测定完整的EV71病毒蛋白1（VP1）编码区序列以进行进一步分析。
在本研究分离出的126株肠道病毒中，鉴定出58株EV71毒株（46%）。测定了46株EV71毒株的完整VP1序列并进行了基因分析。结果显示，46株宁夏毒株与A、B基因型代表株的核苷酸同源性分别为81.7% - 82.8%和83.1% - 85.2%，氨基酸同源性分别为93.9% - 95.9%和96.2% - 97.9%。宁夏EV71分离株与C1、C2、C3、C4a、C4b和C5亚型代表株的核苷酸同源性分别为88.3% - 90.6%（97.9% - 99.6%）、88.3% - 90.1%（97.9% - 99.3%）、87.8% - 89.0%（97.6% - 98.9%）、94.2% - 98.9%（97.9% - 100%）、91.8% - 94.1%（98.6% - 99.6%）和86.7% - 89.1%（97.9% - 98.9%）。系统发育树分析显示，46株毒株与C4亚型参考毒株聚类，宁夏EV71分离株属于C4a亚型。
C4a亚型EV71于2009年在宁夏广泛传播，是2009年宁夏的绝对优势型，也是自2005年以来中国大陆的优势型。
