Abstract：
Coxsackievirus A16 (CV-A16) is a significant etiologic agent of hand, foot, and mouth disease (HFMD) and herpangina (HA), with the capacity to progress to severe complications, including encephalitis, aseptic meningitis, acute flaccid paralysis, myocarditis, and other critical conditions. Beijing\'s epidemiological surveillance system, established in 2008, encompasses 29 hospitals and 16 district disease control centers. From 2019 to 2021, the circulation of CV-A16 was characterized by the co-circulation of B1a and B1b clades. Multiple cases of HFMD linked to clade B1c has not been reported in Beijing until 2022. This study enrolled 400 HFMD and 493 HA cases. Employing real-time RT-PCR, 368 enterovirus-positive cases were identified, with 180 selected for sequencing. CV-A16 was detected in 18.89% (34/180) of the cases, second only to CV-A6, identified in 63.33% (114/180). Full-length VP1 gene sequences were successfully amplified and sequenced in 22 cases, revealing the presence of clades B1a, B1b, and B1c in 14, 3, and 5 cases, respectively. A cluster of five B1c clade cases occurred between June 29 and July 17, 2022, within a 7-km diameter region in Shunyi District. Phylogenetic analysis of five complete VP1 gene sequences and two full-genome sequences revealed close clustering with the 2018 Indian strain (GenBank accession: MH780757.1) within the B1c India branch, with NCBI BLAST results showing over 98% similarity. Comparative sequence analysis identified three unique amino acid variations (P3S, V25A, and I235V). The 2022 Shunyi District HFMD cases represent the first instances of spatiotemporally correlated CV-A16 B1c clade infections in Beijing, underscoring the necessity for heightened surveillance of B1c clade CV-A16 in HFMD and HA in this region.
摘要：
柯萨奇病毒A16（CV-A16）是一种重要的手部病原体，脚,和口蹄疫（HFMD）和疱疹性咽峡炎（HA），有能力发展为严重的并发症，包括脑炎,无菌性脑膜炎,急性弛缓性麻痹,心肌炎,和其他关键条件。北京市流行病学监测系统,成立于2008年，包括29家医院和16个地区疾病控制中心。从2019年到2021年，CV-A16的循环特征是B1a和B1b进化枝的共同循环。直到2022年，北京才报告与进化枝B1c相关的多例手足口病病例。这项研究纳入了400例HFMD和493例HA病例。采用实时RT-PCR，共发现368例肠道病毒阳性病例,选择180个进行测序。在18.89%(34/180)的病例中检出CV-A16,仅次于CV-A6，占63.33%(114/180)。22例VP1基因全长序列成功扩增并测序,揭示了进化枝B1a的存在，B1b,和B1c在14、3和5例中，分别。2022年6月29日至7月17日，顺义区7公里直径区域内发生了5例B1c进化枝病例。对五个完整的VP1基因序列和两个全基因组序列的系统发育分析显示，在B1c印度分支内与2018年印度菌株（GenBank登录名：MH780757.1）紧密聚类，NCBIBLAST结果显示超过98%的相似性。比较序列分析确定了三个独特的氨基酸变异(P3S，V25A,和I235V）。2022年顺义区手足口病病例是北京首例时空相关CV-A16B1c进化枝感染病例，强调在该地区的HFMD和HA中加强对B1c进化枝CV-A16的监测的必要性。
