145例新型冠状病毒肺炎病例流行特征分析

Epidemic characteristics of 145 COVID-19 cases

目的对西安市新型冠状病毒肺炎(简称新冠肺炎,COVID-19)疫情流行特征进行分析,为更好地防控疫情提供参考。方法采用描述性流行病学方法对疫情应急处置期间病例的现场流行病学调查资料进行分析。结果截至7月25日全市共报告COVID-19病例145例,含确诊病例120例,无症状感染者25例;湖北输入病例42例,其他省市输入病例8例,本地继发病例84例,感染来源不明确者11例;27起聚集性疫情涉及病例116例;死亡3例。输入病例和本地继发病例分别于1月23日-29日和1月26日-2月4日出现发病高峰,分别为27例和44例;未央区、莲湖区、新城区和雁塔区报告病例数居全市前四位,共占54.48%(79/145);45~54岁者占全部病例22.76%(33/145)。病例从发病到首诊,发病到隔离,首诊到隔离,发病到确诊,首诊到确诊和隔离到确诊的时间依次为1.33(0.17,3.67)d,3.04(0.59,5.18)d,0.04(0.02,2.00)d,5.50(2.56,9.50)d,3.17(1.56,5.84)d和1.63(1.32,3.35)d。结论聚集性发病是西安市COVID-19疫情最重要的流行特征。应急响应后西安市医疗系统接诊后的处置和诊断迅速有力,全市今后的防控重心是防止境外病例输入。

Objective To analyze the epidemic features of coronavirus disease 2019(COVID-19)in Xi’an City,and to provide references for better prevention and control of the epidemic.Methods Descriptive epidemiological methods were used to analyze the data regarding field epidemiological investigation reports of COVID-19 cases during the emergency treatment of epidemic situation.Results As of July 25,a total of 145 COVID-19 cases,including 120 confirmed cases and 25 asymptomatic cases,were reported in Xi’an City.There were 42 imported cases from Hubei Province,8 imported cases from other provinces or cities,84 local secondary cases,and 11 cases with unclear source of infection.And 27 COVID-19 clusters with 116 cases were reported,too.There were 3 deaths.The number of imported cases and local secondary cases peaked from January 23 to 29(27 cases)and from January 26 to February 4(44 cases),respectively.The numbers of reported cases in Weiyang District,Lianhu District,Xincheng District and Yanta District ranked the top four in Xi’an City,totally accounting for 54.48%(79/145).Patients aged 45-54 years accounted for 22.76%of the total cases(33/145).The median interval from symptom onset to first diagnosis was 1.33(0.17,3.67)days,from symptom onset to isolation 3.04(0.59,5.18)days,from first-diagnosis to isolation 0.04(0.02,2.00)days,from symptom onset to confirmed diagnosis 5.50(2.56,9.50)days,from first-diagnosis to confirmed diagnosis 3.17(1.56,5.84)days,and from isolation to confirmed diagnosis 1.63(1.32,3.35)days.Conclusion The most important feature of the COVID-19 epidemic in Xi’an City was cluster outbreak.After the emergency response,treatment and confirmed diagnosis of COVID-19 in the medical institutions in Xi’an City are rapid and effective.Preventing imported cases from oversea is still the focus of future efforts in Xi’an City.