深圳市419例新型冠状病毒肺炎患者流行病学特征分析

Epidemiological characteristics of 419 patients with COVID-19 in Shenzhen

目的分析深圳市新型冠状病毒肺炎(COVID-19)的流行趋势和流行病学特征。方法收集2020年3月10日前深圳市COVID-19疫情信息和419例确诊患者的基本特征。依据每日确诊的病例数区分不同的流行阶段(时期),根据患者的流行病学调查资料判读传染的方式,估计患者的潜伏期,比较不同流行阶段患者传染方式和人群特征的变化。结果深圳市COVID-19患者主要是湖北输入性病例(73.7%)及其密切接触者(主要是家属,13.4%),患者平均年龄是45.4岁,家庭感染病例的比例为55.4%。推测COVID-19患者的暴露时间集中在1月20日左右,中位潜伏时间为7 d。依据每日确诊病例数把深圳市COVID-19疫情分为3个阶段:疫情早期、爆发期和后期。在3个阶段中,尽管与湖北相关的病例一直是占主要的比例,但与湖北无关的患者比例在后期逐渐升高,家庭感染病例的比例逐渐升高,患者的年龄逐渐下降,差异均有统计学意义(P值均<0.05)。后期逐渐出现境外输入性病例。结论深圳市COVID-19输入性病例的比例全国最高,湖北输入性病例和家庭聚集感染是深圳市COVID-19最主要的传播途径,后期非湖北相关的病例增加且出现境外输入病例。这些特点可以作为疫情控制策略制定的学术依据,提高防控的效率。

Objective To describe the epidemic trend and epidemiological characteristics of the COVID-19 in Shenzhen.Methods The epidemiological characteristics of 419 confirmed patients in Shenzhen before March 10,2020 were collected.The daily new cases were used to distinguish the different epidemic stages(periods)of COVID-19,the epidemiological investigation data of patients were used to judge the mode of infection and estimated the incubation period.The infection mode and epidemiological characteristics in different epidemic stages were compared.Results The COVID-19 patients in Shenzhen were mainly imported cases from Hubei(73.7%)and their close contacts(mainly family members,13.4%),the average age of patients was 45.4 years,and the proportion of family infection cases was 55.4%.The estimated exposure time of patients was concentrated around January 20,with a median incubation period of 7 days.Based on the daily new cases,three phases were classified:early phase,outbreak phase and late phase.In the three stages,although the cases related with Hubei have been the main proportion,the proportion of patients unrelated with Hubei gradually increased in the later stage,the proportion of familial infection cases gradually increased,and the age of patients gradually decreased.These differences were statistically significant(all P<0.05).In the late stage,imported cases gradually appeared.Conclusions The proportion of imported cases in Shenzhen is the highest in China.The imported cases from Hubei and familial cluster infection are the main transmission routes of COVID-19 in Shenzhen.The patients unrelated with Hubei increased and imported cases from abroad occurred in the late stage.These characteristics can be used as the academic basis for epidemic control strategies and improve the efficiency of prevention and control.