Investigation of an epidemic cluster caused by COVID-19 cases in incubation period in Shanghai
10.3760/cma.j.cn112338-20200302-00236
- VernacularTitle:上海市一起潜伏期病例传播的新型冠状病毒肺炎聚集性疫情调查
- Author:
Wenjia XIAO
1
;
Qiang GAO
;
Kai JIN
;
Xiaohuan GONG
;
Ruobing HAN
;
Chenyan JIANG
;
Xianjin JIANG
;
Bihong JIN
;
Qiwen FANG
;
Hao PAN
;
Huanyu WU
;
Xiaodong SUN
Author Information
1. 上海市疾病预防控制中心传染病防治所 200336
- Keywords:
COVID-19;
Epidemic cluster;
Incubation period;
Transmission
- From:
Chinese Journal of Epidemiology
2020;41(9):1401-1405
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To analyze the epidemiological characteristics of a cluster of 5 confirmed COVID-19 cases related with the transmission in incubation period of initial case, and find out the infection source and transmission chain.Methods:According to "The Prevention and Control Protocol for Coronavirus Disease 2019 (Third Edition)" issued by the National Health Commission, a field epidemiological survey was conducted for the 5 cases in January 2020. Nasopharyngeal swabs and sputum samples were collected from them for the detection of 2019-nCoV by real time RT-PCR. Multi prevention and control measures were taken, such as tracking and screening close contacts, medical isolation observation, investigating the epidemiological link, analyzing transmission chain.Results:Case 1, who had common environmental exposure with other COVID-19 cases, got sick on 20 January, 2020 and was confirmed on 1 February. Case 2 became symptomatic on 22 January and was confirmed on 27 January. Case 3 got sick on 25 January and was confirmed on 30 January. Case 4 had illness onset on 20 January and was confirmed on 1 February. Case 5 got sick on 23 January and was confirmed on 31 January. Among the 5 cases, case 2 died and the illness of other cases were effectively controlled. After exclusion of other common exposure factors, case 1 had a 6-hour meeting with case 2 and case 3 on 19 January. Case 2 and case 3 might be infected by case 1 during the incubation period. It is the key point for epidemiological investigation.Conclusion:The epidemiological investigation indicates that the transmission might occur in the incubation period of COVID-19 case, close attention should be paid to it in future COVID-19 prevention and control.
