新型冠状病毒肺炎聚集性疫情特征初步分析

新型冠状病毒肺炎作为新发传染病,自2019年12月发现以来,全球27个国家和地区已有病例报告。随着疫情的发展,聚集性疫情所占的发病数比例不断增加,尤其是武汉市和湖北省以外地区,暴露来源发生很大变化。本研究收集2020年1月1日至2月20日期间非医疗机构新型冠状病毒肺炎聚集性疫情377起（涉及病例1 719例）进行分析。其中,家庭聚集性疫情297起（占79%）,确诊病例中位数为4例;聚餐39起（占10%）,确诊病例中位数为5例;商场或超市23起（占6%）,确诊病例中位数为13例;工作单位12起（占3%）,确诊病例中位数为6例;交通工具6起（占2%）,确诊病例中位数为6例。依聚集性病例潜伏期估计所需条件,选出325例,推测潜伏期为1~20 d,中位数为7 d,众数为4 d。此外,对国内某百货大楼聚集疫情分析结果提示本次疫情潜伏期患者可能成为传染源。"钻石公主"号邮轮聚集疫情从2月5-21日共634人被确诊感染,各类人群（国籍、年龄、性别）均易感,提示乘客年龄、无症状感染及邮轮内封闭环境可能是导致邮轮后续病例出现间歇同源暴露和人传人增殖模式的主要原因,两起典型疫情的进展清晰地展现了武汉早期病例的播散情况。因此,在疫情防控中,除隔离患者外,追踪、排查和隔离密切接触者及次级接触者至关重要;尤其对于疫区的健康人群,自我隔离是防控关键。

The preliminary analysis on the characteristics of the cluster for the COVID-19

Since December 2019, COVID-19, a new emerging infection disease, has spread in 27 countries and regions. The clusters of many cases were reported with the epidemic progresses. We collected currently available information for 377 COVID-19 clusters (1 719 cases), excluded the hospital clusters and Hubei cases, during the period from January 1 to February 20, 2020. There were 297 family clusters (79%), case median was 4; 39 clusters of dining (10%), case median was 5; 23 clusters of shopping malls or supermarkets (6%), case median was 13; 12 clusters of work units (3%), case median was 6, and 6 clusters of transportation. We selected 325 cases to estimate the incubation period and its range was 1 to 20 days, median was 7 days, and mode was 4 days. The analysis of the epidemic situation in a department store in China indicated that there was a possibility of patients as the source of infection during the incubation period of the epidemic. From February 5 to 21, 2020, 634 persons were infected on the Diamond Princess Liner. All persons are susceptible to the 2019 coronavirus. Age, patients during the incubation period and the worse environment might be the cause of the cases rising. The progress of the two typical outbreaks clearly demonstrated the spread of the early cases in Wuhan. In conclusion, screening and isolating close contacts remained essential other than clinical treatment during the epidemic. Especially for the healthy people in the epidemic area, isolation was the key.