1起由冷链产品引起的新型冠状病毒Omicron BA.2.3.7感染的传播链和基因序列分析

Chain of transmission and gene sequence analysis of SARS-CoV-2 Omicron BA.2.3.7 infection caused by a cold chain product

目的对福建省福州市M区1起由进口冷链产品引起的新型冠状病毒暴发疫情进行溯源及基因序列分析。方法收集2022年9月6日至9月9日期间M区新冠疫情中全部感染者(8名)以及1份阳性冷链产品样本拭子,进行流行病学调查,对采集到的样本进行实时荧光定量PCR检测,对3例阳性感染者和1份冷链产品样本进行全基因组序列测序分析。结果该起疫情共有8人感染,均为无症状感染者,4条全基因组序列高度同源,共享75个的核苷酸突变位点,共享55个氨基酸突变位点,且符合谱系BA.2.3.7的特征。结论本次疫情由未有效防护的工人暴露于污染了新型冠状病毒Omicron BA.2.3.7的进口冷链产品所引起。

The aim of this study was to trace to origin of SARS-CoV-2 originating from imported cold-chain products responsible for an outbreak that occurred on September 6-9,2022 in Mawei District,Fuzhou City,Fujian Province,China.Samples from all positively infected persons and one positive sample from a swab of a cold-chain product during the outbreak were collected for gene sequencing.Epidemiological investigations were conducted on all positively infected persons to analyze the chain of transmission of the virus.Nucleic acids were detected by real-time fluorescence quantitative PCR,and the outbreak was characterized by a total of eight positive infections,which were asymptomatic.Whole-genome sequencing of three infected persons and one cold-chain product sample identified 75 nucleotides and 55 amino acid mutation sites of the BA.2.3.7 variant,with four highly homologous whole-genome sequences.These results confirmed that the outbreak was caused by exposure to imported cold-chain products carrying the SARS-CoV-2 Omicron BA.2.3.7 strain.