四川省成都市境外输入新型冠状病毒肺炎病例流行病学特征分析

Epidemiological characteristics of imported cases of coronavirus disease 2019 in Chengdu,Sichuan

目的分析四川省成都市境外输入新型冠状病毒肺炎(COVID-19)病例的流行病学特征,为科学开展疫情防控提供依据。方法收集截至2020年11月30日成都市入境航班及境外输入病例相关信息,采用Epidata Manager、WPS 2019和R 4.0.3软件进行数据管理和统计分析。结果截至2020年11月30日,成都市累计入境航班677班次(含包机44班次),来自36个国家或地区,累计入境90900人。病例主要来自亚洲地区(63.98%,58154/90900),非洲地区来成都航班人员患病率(1.09%,141/12890)较高(χ^(2)=133.137,P<0.001)。136班次航班报告COVID-19病例,单次航班最多报告36例,单日最高报告病例数为25例。成都市报告境外输入确诊病例占全国同期境外输入病例的6.88%(266/3866),多数病例症状轻微,有60.90%(162/266)的病例无自觉临床症状,多以肺部CT异常而确诊。成都市73.97%(324/438)的境外输入病例由入境口岸检疫初筛阳性后确诊,共涉及38起聚集性疫情,以男性(82.89%,373/450)、年龄20~50岁(80.00%,360/450)、工人(40.89%,184/450)病例为主。结论成都市境外输入病例较多,病例大多症状轻微,多来自非洲和亚洲国家(或地区),加强入境口岸筛查和密切接触筛查对控制成都市乃至全国疫情都具有重要意义。

Objective To understand the epidemiological characteristics of imported coronavirus disease 2019(COVID-19)cases detected in Chengdu,Sichuan,and provide scientific basis for the prevention and control of COVID-19.Methods The data of imported COVID-19 cases in Chengdu were obtained from National Notifiable Disease Report System of China CDC,field epidemiological investigation reports by CDCs in Chengdu,and flight related information from Chengdu airport.Software Epidata Manager,WPS 2019 and R 4.0.3 were used for data management and statistical analysis.Descriptive statistics andχ2 test were used to analyze the characteristics of the imported cases and inbound flights.Results As of November 30,2020,a total of 90900 passengers from 36 countries and regions via 677 inbound flights(including 44 chartered airplane flights)had entered China at Chengdu Shuangliu International Airport.The passengers were mainly from Asia(63.98%,58154/90900),but the attack rate in flights from Africa was relatively high(χ2=133.137,P<0.001).Of the 677 flights,136 flights had imported COVID-19 cases.The maximum of case number on one flight was 36,and the maximum daily case number was 25.The imported COVID-19 cases detected in Chengdu accounted for 6.88%of the total imported cases in China during the same period.Most cases had mild symptoms,and 162(60.90%)were sub-clinical,most cases were diagnosed by chest CT.Up to 73.97%(324/438)of imported cases in Chengdu were diagnosed after the custom port preliminary quarantine screening,involving 38 clusters.The imported COVID-19 cases detected in Chengdu were mainly males(82.89%,373/450),aged 20-50 years old(80.00%,360/450)and workers(40.89%,184/450).Most cases were not local residents.Conclusion The imported cases of COVID-19 detected in Chengdu were mainly from countries or regions in Africa and Asia.Majority of the cases were sub-clinical,so strengthening the port case screening and close contact screening are essential to the prevention and control of COVID-19 in Chengdu,even in China.