JI Zhen-hao1, LEI Rui-jie2, CHEN Zhi-jun1, LIU Ji-feng1, SUN Ya-hui1, ZHANG Hui1, ZHAO Xin1, XUE Ze-run1
1. Xi'an Municipal Center for Disease Control and Prevention, Xi'an, Shaanxi 710054, China; 2. The Fourth Hospital of Xi'an City, Xi'an, Shaanxi 710004, China
Abstract: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 firstdiagnosis 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.
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