一起新型冠状病毒肺炎聚集性疫情调查

Clustering of coronavirus disease 2019:a brief report

目的通过对Y市一起新型冠状病毒肺炎聚集性疫情的调查,初步分析该病潜伏期、传染期、传播能力。方法应用现场流行病学方法调查病例及其密切接触者,采用实时荧光RT-PCR技术对采集咽拭子标本进行新型冠状病毒核酸检测。结果本起疫情一共发现13名确诊病例和4名无症状感染者,发生四代病例传播,平均代际间隔时间5.08 d,平均潜伏期5.44 d(2~10 d),部分病例发病前2 d已具备传染性;密切接触者中存在一定比例隐性感染者。病例检测时存在需要多次采样检测方能确诊的现象。结论新型冠状病毒传播能力强,存在潜伏期传播,存在无症状感染,需加强对密切接触者的追踪、管理等防控措施。

Objective To preliminarily analyze the latent period,infectious period and transmissibility of coronavirus disease 2019(COVID-19)through an investigation of a clustering epidemic of COVID-19 in Y city.Methods Field epidemiological method was used to survey the cases and related close contacts.Real time RT-PCR technique was used to detect 2019-nCoV nucleic acid in throat swab samples collected from the respondents.Results A total of 13 confirmed cases and 4 asymptomatic infections were discovered in the clustering epidemic,with the transmission passing through four generations.The average serial interval was 5.08 days,and the average incubation period 5.44 days(ranging between 2 and 10 days).Some confirmed cases were found to be contagious 2 days prior to the onset.There were some asymptomatic infections among the close contacts.Some cases were confirmed after several times of sample testing.Conclusions 2019-nCoV has a high transmissibility.There exist transmission during the incubation period and asymptomatic infection.It is necessary to intensify the prevention and control measures like follow-up and management of close contacts.