2013年西安地区柯萨奇病毒A6流行情况及基因特征

Circulation status and genetic characteristics of coxsackievirus A6 in Xi'an in 2013

目的 研究2013年西安地区普通手足口病（HFMD）病例中柯萨奇病毒A6型（CA6）的流行情况及其基因特征.方法 从2013年采集的普通HFMD病例标本中随机挑选250份非肠道病毒71型（EV71）非柯萨奇病毒A16型（CA16）的其他肠道病毒核酸阳性者,利用实时荧光逆转录酶联聚合反应检测CA6,扩增部分阳性标本VP1 （viral protein,VP）基因,并测定序列,与CA6其他参考序列比对,进行进化分析.结果 在250份样本中CA6阳性者共191份,阳性率为76.4％.进化分析显示西安地区2013年CA6与近年来流行于世界各地的CA6新变种同源性较高,而与原型株进化距离较远.序列比对发现本地毒株VP1与CA6新变种核苷酸序列相似性在89.7％～97.5％,编码氨基酸相似性为96.0％～99.7％;与CA6原型株及2006年以前中国大陆分离株核苷酸相似性为82.3％～83.8％,氨基酸相似性为93.8％～94.9％.结论 2013年西安地区HFMD普通病例病原以CA6为主,流行株为近年来流行于全球各地的CA6新变种.

Objective To study the circulation status and genetic characteristics of coxsackievirus A6 （CA6） in Xi＇an in 2013.Methods CA6 nucleotide was detected by real time RT-PCR in 250 non-enterovirus 71 （EV71） non-CA16 enterovirus nucleotide positive samples collected in 2013,and viral protein （VP） 1 of CA6 was sequenced and phyletic evolution was analyzed.Results The results showed that 191 out of 250 samples were CA6 positive,which accounted for 76.4％ in common HFMD patients.VP1 of CA6 was clustered in the same clade on phyletic tree,and compared with the new variant of CA6 circulating in many places around the world recently,the nucleotide sequences had 89.7％-97.5％ similarity and the amino acid sequence deduced had 96.0％-99.7％ similarity.Compared with the strains circulated in China's Mainland before 2006,the nucleotide and amino acid sequence similarity were 82.3％-83.8％ and 93.8％-94.9％ respectively.Conclusion In 2013,the main aetiological agent of common HFMD in Xi＇an was the new variant of CA6.