Liu Pengcheng, Cai Jiehao, Tian He, Li Jingjing, Lu Lijuan, Xu Menghua, Zhu Xunhua, Fu Xiaomin, Wang Xiangshi, Zhong Huaqing, Jia Ran, Ge Yanling, Zhu Yanfeng, Zeng Mei, Xu Jin
Department of Clinical Laboratory, National Children's Medical Center, Children's Hospital of Fudan University, Shanghai, China.
Department of Infectious Diseases, National Children's Medical Center, Children's Hospital of Fudan University, Shanghai, China.
Front Microbiol. 2024 Mar 28;15:1372078. doi: 10.3389/fmicb.2024.1372078. eCollection 2024.
An unprecedented surge of Omicron infections appeared nationwide in China in December 2022 after the adjustment of the COVID-19 response policy. Here, we report the clinical and genomic characteristics of SARS-CoV-2 infections among children in Shanghai during this outbreak.
A total of 64 children with symptomatic COVID-19 were enrolled. SARS-CoV-2 whole genome sequences were obtained using next-generation sequencing (NGS) technology. Patient demographics and clinical characteristics were compared between variants. Phylogenetic tree, mutation spectrum, and the impact of unique mutations on SARS-CoV-2 proteins were analysed in silico.
The genomic monitoring revealed that the emerging BA.5.2.48 and BF.7.14 were the dominant variants. The BA.5.2.48 infections were more frequently observed to experience vomiting/diarrhea and less frequently present cough compared to the BF.7.14 infections among patients without comorbidities in the study. The high-frequency unique non-synonymous mutations were present in BA.5.2.48 (N:Q241K) and BF.7.14 (nsp2:V94L, nsp12:L247F, S:C1243F, ORF7a:H47Y) with respect to their parental lineages. Of these mutations, S:C1243F, nsp12:L247F, and ORF7a:H47Y protein were predicted to have a deleterious effect on the protein function. Besides, nsp2:V94L and nsp12:L247F were predicted to destabilize the proteins.
Further in vitro to in vivo studies are needed to verify the role of these specific mutations in viral fitness. In addition, continuous genomic monitoring and clinical manifestation assessments of the emerging variants will still be crucial for the effective responses to the ongoing COVID-19 pandemic.
2022年12月中国新冠疫情防控政策调整后，奥密克戎感染病例在全国范围内出现了前所未有的激增。在此，我们报告了此次疫情期间上海儿童感染新型冠状病毒的临床和基因组特征。
共纳入64例有症状的新冠患儿。采用下一代测序（NGS）技术获取新型冠状病毒全基因组序列。比较不同变异株之间的患者人口统计学和临床特征。利用计算机分析系统发育树、突变谱以及独特突变对新型冠状病毒蛋白的影响。
基因组监测显示，新出现的BA.5.2.48和BF.7.14是主要变异株。在本研究中，与BF.7.14感染相比，在无合并症的患者中，BA.5.2.48感染更常出现呕吐/腹泻，咳嗽症状出现频率较低。相对于其亲本谱系，BA.5.2.48（N：Q241K）和BF.7.14（nsp2：V94L、nsp12：L247F、S：C1243F、ORF7a：H47Y）存在高频独特非同义突变。在这些突变中，S：C1243F、nsp12：L247F和ORF7a：H47Y蛋白预计对蛋白功能有有害影响。此外，nsp2：V94L和nsp12：L247F预计会使蛋白不稳定。
需要进一步开展体外到体内的研究，以验证这些特定突变在病毒适应性中的作用。此外，对新出现变异株进行持续的基因组监测和临床表现评估，对于有效应对当前的新冠疫情仍至关重要。
