广东省惠州市一起无症状感染者引起新型冠状病毒肺炎家庭聚集性疫情分析

A familial cluster with COVID-19 caused by asymptomatic infection in Huizhou,Guangdong

目的对惠州市一起无症状感染者引起的新型冠状病毒肺炎(COVID-19)家庭聚集性疫情进行流行病学调查和分析,为COVID-19疫情防控积累经验。方法对该起疫情所有病例及其密切接触者进行现场流行病学调查,并采集鼻咽拭子、咽拭子、肛拭子和血液标本,对一般接触者采集咽试子标本,采用RT-PCR法进行新型冠状病毒(SARSCOV-2)核酸检测和胶体金法检测IgM抗体和IgG抗体。结果本起疫情共有1例确诊病例,2例无症状感染者;传染源可能是具有武汉居住史的无症状感染者C,并较大可能通过密切接触方式传染给无症状感染者B,由B传染给确诊病例A,但不排除由C先后传染给B和A;A是该起疫情的指示病例;根据流行病学调查和SARS-COV-2核酸检测以及血液标本IgM、IgG检测判定,本疫情为一起输入性无症状感染者导致本地感染的家庭聚集性疫情。结论家庭聚集性疫情以密切接触方式传播为主,加强对家庭的个人卫生防护宣传;家庭聚集性疫情中如果存在无症状感染者其传染具有一定隐蔽性,是社区扩散的重要风险点,应加强对无症状感染者的管理,特别是对无症状感染者儿童应重视早期识别。

Objective To investigate the epidemiological characteristics of a family cluster of COVID-19 in Huizhou,in order to propose the prevention and control measures,we also accumulate experience to deal with family cluster cases.Methods Field epidemiological survey was conducted,and sampling of nasopharyngeal,throat,anal swabs and blood specimens.We were sampling of throat swabs in general contact,detection SARS-COV-2 by RT-PCR,and serum antibody IgM and IgG were detected by colloidal gold method.ResultsThere are 1 confirmed case and 2 asymptomatic infected cases in this family cluster.The source of infection may be asymptomatic infected case C with a living history in Wuhan,and it is likely transmitted to asymptomatic infected case B through close contact,and then it is transmitted to case A by case B.But it is not excluded that C has been successively transmitted to B and A.The case A is the indicator of this family cluster epidemic.Determined based on epidemiological investigations,SARS-COV-2 nucleic acid testing and IgM/IgG testing of blood samples,This case is a family cluster epidemic leading to autochthonous infection by imported asymptomatic infection.Conclusion The close contacts were the main transmission mode in family cluster,it is need to strengthen the publicity of personal health protection for families;There is a certain proportion of asymptomatic infections within family cluster,and the asymptomatic infection is highly hidden,it will be important risk for community spread.It is necessary to strengthen the management of asymptomatic infection,especially for identifying children with asymptomatic infection in the early stage.