2020—2022年广西境外输入新型冠状病毒感染者流行病学和基因特征分析

Epidemiological and genetic characteristics analysis of imported COVID-19cases in Guangxi Zhuang Autonomous Region,2020-2022

目的分析广西境外输入新型冠状病毒(简称新冠病毒)感染者的流行病学和基因特征,评价境外输入病例对本土疫情的影响。方法从“中国疾控预防控制信息系统”中收集2020年3月1日—2022年12月6日广西境外输入新冠病毒感染者和聚集性疫情的相关信息,使用SPSS 20.0软件进行流行病学特征分析,用Javascript语言在Echart绘图网页绘制桑基图。使用CLC Genomics Workbench(Version 21.0.4)软件进行序列拼接,使用MEGA7.0软件构建系统进化树。结果广西共报告境外输入新冠病毒感染者4424例,其中确诊病例1023例、无症状感染者3401例。确诊病例中,以轻型(52.7%)和普通型(47.0%)为主。男女比例为6.2∶1,平均年龄37.8岁,以36~59岁为主,占比53.6%。78.3%感染者接种过疫苗。来源国主要为越南,占95.8%,入境口岸主要是凭祥友谊关(4012例,90.7%)。127起聚集性疫情累计发病6720例,其中经接触境外物品和人员引起的26起,累计发病3007例。共累计获得了241条有效的全基因组序列,聚类为44个进化分支。病原谱分析显示排在前3位的进化分支分别为BA.5.2、AY.57和BA.2。系统发育分析表明,这些境外输入新冠病毒感染者的序列与输出国(来源国)的毒株序列高度同源。结论广西持续存在输入疫情的风险,且新冠病毒易于突变,持续做好输入病毒变异监测至关重要。

Objective To analyze the epidemiological and genetic characteristics of imported COVID-19 cases in Guangxi,and evaluate the impact of imported cases on the local epidemic.Methods The data of imported COVID-19 cases and clustered epidemics reported in Guangxi from March 1,2020 to December 6,2022 were collected from the“China Disease Control and Prevention Information System”.Epidemiological characteristics were performed using SPSS 20.0.Javascript by Echart web tool was used to draw Sankey diagram.CLC Genomics Workbench software was used for sequence assembly.A phylogenetic tree was constructed by MEGA.Results Guangxi reported a total of 4424 imported COVID-19 infection cases,including 1023 confirmed cases and 3401asymptomatic infections.Among the confirmed cases,mild(52.7%)and common(47.0%)were the main types.The male-to-female ratio was 6.2∶1.The mean age of cases was 37.8 years,and most of them were36-59 years old,accounting for 53.62%.78.3%of infected persons had been vaccinated.The country of origin was mainly Vietnam,accounting for 95.8%,and the main port of entry was Pingxiang Youyiguan(4012cases,90.7%).A total of 6720 cases of 127 clustered epidemics occurred,of which 26 cases were caused by contact with foreign objects and personnel,and a total of 3007 cases were diagnosed.A total of 241 valid genome sequences were obtained,clustered into 44 evolutionary branches.Pathogen spectrum analysis showed that the top three evolutionary branches were BA.5.2,AY.57,and BA.2.Phylogenetic analysis showed that the sequences of these imported cases were highly homologous to those of the strains in the countries of origin(source country).Conclusions Guangxi continues to have the risk of imported epidemics,and the SARSCoV-2 is prone to mutations.It is very important to continue to monitor the mutation of imported viruses.