德阳市某县首例输入性新型冠状病毒肺炎家庭内传播的流行病学分析

Analysis on the Epidemiological Features and the Transmission of the First Imported COVID-19 Case in the Family in the County of Deyang City

目的描述性分析家庭内新型冠状病毒肺炎(coronavirus disease 2019,COVID-19)传播过程,探讨其传播规律和流行特征,为做好家庭内疫情防控提供参考依据。方法对德阳市某县首例输入性新型冠状病毒肺炎疫情及其密切接触者进行逐一现场流行病学调查,分析病例之间的关系、接触方式与频率,并采集呼吸道标本(鼻咽拭子)进行实时荧光RTPCR方法检测新型冠状病毒核酸情况。结果该起家庭内聚集性COVID-19疫情由德阳市某县从武汉返乡人员病例A引起,波及80人,续发二代病例4例,罹患率6.25%,分别是病例B(丈夫)、病例C(弟弟)、病例D(弟媳)、病例E(母亲)。在近距离无效防护下,5例病例具有同屋居住、多次同桌就餐、乘车、棋牌娱乐等暴露史,病例特征主要表现以发热、咳嗽、肺炎影像学特征为主;潜伏期最长10 d、最短5 d,中位数8 d。结论接触频率、接触方式是COVID-19的重要影响因素;在无有效防护下,接触频率、接触方式越紧密,其感染COVID-19的可能性越大;疫情期间,建议家庭内成员减少外出、外出时佩戴口罩,并保持一定距离,从而降低传播风险。

Objective The transmission process in a family of(coronavirus disease 2019,COVID-19)coronavirus was analyzed descriptively,to explore its transmission rules and epidemic characteristics,in order to provide the reference for the prevention and control of epidemic situation in family.Methods The first imported case of COVID-19 and its close contacts in a county of Deyang city were investigated and analyzed,the relationship between the cases、mode and frequency of contact were analyzed,Respiratory Tract Specimens(NASOPHARYNGEAL swabs)were collected for the detection of nucleic acid in 2019-ncov(nCoV-2019)by real-time Quantitative RTPCR.Results COVID-19 outbroke in a family in the county of Deyang was caused by a case among the returnees from Wuhan city,about 80 people were affected,and 4 cases were second-generation cases,with a prevalence rate of 6.25%,they were Case B(husband),case C(brother),case D(sister-in-law),case E(mother).Under the situation of nearness ineffective protection,5 cases had a history of sharing a room,eating at the same table,travelling by car,playing chess and card,etc..The characteristics of the cases were mainly fever,cough,pneumonia,the incubation period ranged from the longest 10 days to the shortest 5 days,with a median of 8 days.Conclusion The frequency and mode of contact are the important influencing factors of COVID-19.The closer the contact is,the more likely it is to be infected with COVID-19,during the epidemic,family members are advised to reduce the time to go out,they should wearing masks when go out and keep a certain distance with others,so that to reduce the risk of transmission.