北京市某入境航班人群新型冠状病毒感染情况分析

COVID-19 infections among passengers in an inbound flight to Beijing

目的分析某入境航班的新型冠状病毒感染者的流行病学特征及实验室检测结果,为输入性病例管理提供参考。方法收集北京市2021年8月6日某入境航班所有入境人员的航班座位信息、入住隔离酒店、转运车辆、入境到就医的历次核酸检测结果等信息,使用描述流行病学方法分析入住酒店、转运车辆、航班座位等聚集性信息,分析本次航班出现多次阳性人员的可能原因。结果本次入境航班共检出新型冠状病毒核酸阳性15人,15人归国前均有48 h内核酸阴性结果。初筛阳性时间最早为入境当天,最长为入境第13天,中位数为入境后第3天。入境后8名阳性者的核酸结果在2家机构出现不一致情况,且阳性结果多位于临界值。6名阳性者的初次血清抗体检测结果即高于100(s/co),且呈现下降趋势。未发现15人因转运车辆、隔离房间等原因导致的聚集发病。结论入境早期的核酸筛查能检出大多数的新型冠状病毒感染阳性病例,但应考虑对初筛结果可疑的入境人员采取血清抗体和核酸检测联合筛查策略以区分既往与现症感染。

Objective To understand the epidemiological characteristics and laboratory test results of COVID-19 infections among passengers in an inbound flight to Beijing,and to provide reference for the management of im⁃ported COVID-19 cases.Methods Flight information,centralized quarantine sites,transfer vehicle,labora⁃tory test results,clinical progression and outcome and other information of all passengers in an inbound flight to Beijing on August 6,2021 were collected and analyzed.Results A total of 15 passengers were COVID-19 positive.They were all tested negative for nucleic acid 48 h before boarding.The earliest positive was on the day of entry,and the longest was on the 13th day of entry,with the median of being the 3rd day after entry.There were inconsistent nucleic acid test results of 8 positive passengers reported by two institutions and the CT values were close to cutoff.The initial serum antibody levels were higher than 100(s/co)in 6 positive passengers.No⁃body was infected during transportation and quarantine.Conclusions Nucleic acid testing before boarding the flight should be able to identify majority of positive cases.Accordingly,joint screening strategy such as blood serum antibody test for inbound passengers with suspicious preliminary screening results of COVID-19 should be implemented to determine the infection history of the case.