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目的:研究2016年山东省烟台地区手足口病(hand, foot and mouth disease, HFMD)的病原谱组成特点，分析烟台HFMD病原谱中柯萨奇病毒A组6型(coxsackie virus A group 6 type, CV-A6)流行株的进化及VP1区重要氨基酸位点的变异情况。方法:采用real-time RT-PCR方法，对2016年烟台地区采集于HFMD患者的738份样品进行肠道病毒(enterovirus, EV)核酸检测和分子定型，统计各型EV阳性标本数量及比例。根据EV的优势型别，选取8株CV-A6进行VP1区扩增，并进行核苷酸序列测定和分析，然后进行系统进化分析。结果:从738份标本中检出EV 460份，主要病原构成为柯萨奇病毒A组16型(coxsackie virus A group 16 type, CV-A16)(56.09%，258/460)、肠道病毒A组71型(enterovirus A group 71 type, EV-A71)(13.48%，62/460)、柯萨奇病毒A组10型(coxsackie virus A group 10 type, CV-A10)(10.65%，49/460)、CV-A6(9.57%，44/460)、柯萨奇病毒A组4型(coxsackie virus A group 4 type, CV-A4)(1.96%，9/460)。其中成功分离到8份CV-A6阳性标本毒株，并进行了全长VP1区核苷酸序列分析，8株CV-A6的序列分析结果表明，其核苷酸相似性为96.12%～100%，氨基酸相似性为97.78%～100%。系统进化分析显示8株CV-A6烟台株均属于D基因型中的D3基因亚型。与参考株CVA6-Gdula-AY421764相比，烟台市CVA16分离株VP1第10、14、174、194、279、283、305位氨基酸出现突变。结论:CV-A16、EV-A71、CV-A10、CV-A6是引起2016年烟台地区HFMD发病的常见病原体，本次分离到的CV-A6均属于D基因型中的D3基因亚型。“,”Objective:To investigate the pathogenic spectrum of enteroviruses associated with hand, foot and mouth disease (HFMD) in the Yantai region of Shandong province in 2016, and analyze the evolution of epidemic strains of coxsackie virus group A type 6 (CV-A6) in the pathogenic spectrum of HFMD enteroviruses and the variations of important amino acid sites in the VP1 region.Methods:A total of 738 samples were collected from the patients with HFMD in Yantai region in 2016 to conduct DNA and serotype tests of enterovirus (EV) by real-time RT-PCR and further count the number and proportion of each type of enterovirus positive specimens. Based on the predominant serotype of enteroviruses, eight serotypes of the CV-A6 strains were selected to carry out VP1 regions amplification for the determination and analysis of nucleotide sequencing and phylogenetic analysis.Results:A total of 460 enteroviruses strains were isolated from 738 samples, including pathogens strains: 258 CV-A16 (56.09%), 62 EV-A71 (13.48%), 49 CV-A10 (10.65%), 44 CV-A6 (9.57%) and 9 CV-A4 (1.96%). Eight CV-A6 positive specimens were isolated from the viruses and the nucleotide-sequence analysis of the whole VP1 region was conducted. The sequence analysis of eight CV-A6 strains demonstrated that the homologies of nucleotide and amino acid were 96.12% - 100% and 97.78% - 100% respectively. The phylogenetic analysis indicated that the eight CV-A6 strains were subdivided into the genotype D subtype D3. Compared with the reference strain, CVA6-Gdula-AY421764, amino acids of CV-A6 strains in Yantai city observed at sites 10, 14, 174, 194, 279, 283 and 305 in VP1 region appeared mutant.Conclusions:CV-A16, EV-A71, CV-A10 and CV-A6 were the main common pathogens of HFMD in Yantai region in 2016. All the CV-A6 strains isolated in this study belonged to subtype D3 in genotype D.