摘要目的:从分子层面分析石家庄新型冠状病毒的流行病学特征，揭示此次传播链的源头，为新型冠状病毒肺炎疫情防控提供科学依据。方法:收集2021年1月2—8日来自石家庄市第五医院170例新型冠状病毒感染者共计404份新型冠状病毒核酸阳性样本，采用多重聚合酶链反应靶向测序技术对样本进行深度测序获得病毒一致性序列。采用PANGOLIN分类系统对170个毒株序列进行分析，采用T-test对数据进行统计学分析。结果:在404份新型冠状病毒核酸阳性样本中，356份获得病毒的全长基因组序列（>95%，100×测序深度），剔除重复取样，得到170株全基因组序列，所有样本均属于B.1.1分支。病毒突变数18~22个，大部分突变不改变氨基酸信息。根据基因组突变个数和种类，所有毒株分为48个亚型，其中2个毒株占主导（分别为66株和31株）。结论:本研究中所有新型冠状病毒肺炎患者来自单一源头的境外输入性病例，病毒在社区隐匿传播了一段时间，并且在传播的过程中发生了变异。

abstractsObjective:To analyze the molecular epidemiological characteristics of the Corona virus disease 2019 (COVID-19) cases in Shijiazhuang, which can reveal the origin of the outbreak and provide a scientific basis for COVID-19 prevention and control.Methods:From January 2 to January 8, 2021, a total of 404 samples from 170 COVID-19 cases were collected from the Shijiazhuang Fifth Hospital. The consensus sequence of 2019 novel Coronavirus(2019-nCoV) was obtained through multiplex polymerase chain reaction-based sequencing. The sequences of 170 COVID-19 cases were analyzed by the PANGOLIN, and the data were statistically analyzed by T-test.Results:Among the 404 COVID-19 samples, a total of 356 samples obtained high quality genome sequences (>95%,100×sequencing depth). The whole genome sequences of 170 COVID-19 cases were obtained by eliminating repeated samples. All 170 sequences were recognized as lineage B1.1 using PANGOLIN. The number of single nucleotide polymorphism arrange from 18-22 and most of the single nucleotide polymorphism were synonymous variants. All of 170 genomes could be classified into 48 sub-groups and most of the genomes were classified into 2 sub-groups (66 and 31, respectively).Conclusions:All cases in this study are likely originated from one imported case. The viruses have spread in the community for a long time and have mutated during the community transmission.