Sun Zhenlu, Zhang Guifang, Guo Peijun, Liu Juan, Gao Qiao, Xu Xiaowen, Gong Lianfeng
a Yantai Center for Disease Control and Prevention , Yantai , Shandong Province , PR China.
Hum Vaccin Immunother. 2017 Aug 3;13(8):1831-1838. doi: 10.1080/21645515.2017.1318233. Epub 2017 May 24.
This study aimed to investigate the epidemiological characterizations and pathogen spectrum of hand, foot, and mouth disease (HFMD) in Yantai City, Shandong Province, China, during 2011-2015, and to study the nucleotide evolution and amino acid variation of coxsackievirus A16 (CV-A16) epidemic strains that caused HFMD. The HFMD epidemic began to rise in March, and became prevalent from May to August, reached its peak in June, and then declined in September every year, children aged one to 5 years-old had the highest incidence rate whereas the incidence in children under 6 months was very low, and there were more males than females. Enterovirus nucleic acid detection using real-time reverse transcription polymerase chain reaction was performed on 2130 clinical specimens collected from patients with HFMD between 2011 and 2015, and 2012 enterovirus positive samples were detected, including 678 CV-A16, 639 EV-A71, and 695 other enteroviruses. In total, 60 CV-A16 isolates were randomly selected each year for virus isolation, of which 33 CV-A16 strains were randomly selected for further characterization because CV-A16 is the predominant serotype that caused HFMD in Yantai City, and a phylogenetic tree based on the VP1 region was constructed. All 33 CV-A16 strains belonged to the Bla and B1b genotypes, with a nucleotide similarity of 87.9-100% and deduced amino acid similarity of 98.6-100%. Compared with the reference strain Tainan/5079/98 (AF177911), amino acid mutations were identified at positions 11, 23, 25, 31, 99, 145, and 289, where differences were observed among 33 strains, indicating a unique mutation map of CV-A16 in Yantai City. Our findings demonstrate the etiologic characteristics of HFMD, provide supporting evidence for the prevention and control of HFMD, and open a promising avenue for vaccine development against HFMD, by targeting CV-A16.
本研究旨在调查2011 - 2015年中国山东省烟台市手足口病（HFMD）的流行病学特征和病原体谱，并研究引起手足口病的柯萨奇病毒A16（CV - A16）流行株的核苷酸进化和氨基酸变异。手足口病疫情于3月开始上升，5月至8月流行，6月达到高峰，然后每年9月下降，1至5岁儿童发病率最高，而6个月以下儿童发病率很低，且男性多于女性。对2011年至2015年从手足口病患者中收集的2130份临床标本进行实时逆转录聚合酶链反应检测肠道病毒核酸，检测到2012份肠道病毒阳性样本，其中包括678份CV - A16、639份EV - A71和695份其他肠道病毒。每年随机选择60份CV - A16分离株进行病毒分离，其中33份CV - A16菌株被随机选择进行进一步鉴定，因为CV - A16是烟台市引起手足口病的主要血清型，并构建基于VP1区域的系统发育树。所有33份CV - A16菌株均属于B1a和B1b基因型，核苷酸相似性为87.9% - 100%，推导的氨基酸相似性为98.6% - 100%。与参考株台南/5079/98（AF177911）相比，在第11、23、25、31、99、145和289位鉴定出氨基酸突变，33株之间存在差异，表明烟台市CV - A16具有独特的突变图谱。我们的研究结果证明了手足口病的病因特征，为手足口病的预防和控制提供了支持证据，并通过针对CV - A16为开发手足口病疫苗开辟了一条有前景的途径。
