一线城市新型冠状病毒肺炎实时基本再生数估算及流行现状评估

Estimation of real-time basic reproduction number and epidemic status of 2019 novel coronavirus diseases(COVID-19) in first-tier cities

目的对北京市、上海市、广州市、深圳市新型冠状病毒肺炎流行趋势及防控现状进行分析,为疫情防控提供相关基础数据。方法基于卫生健康委员会官方网站公布的疫情数据,运用成熟的模型估计不同时间基本再生数(basic reproduction number,R0)的动态变化R0(t),以评估在现有防控措施下,新型冠状病毒肺炎传染性随时间的变化趋势。结果截至2020年2月25日24时,北京、上海、广州、深圳4个城市累计确诊新冠病毒肺炎病例分别为400例、336例、346例、417例。4个城市在2020年1月30日-2月2日出现单日确诊最高值,新增病例数从2月份开始普遍进入下降期。2月3日和2月10日之后的3~5 d内,4个城市每日新增病例数均有短暂上升趋势。北京、上海、广州市R0(t)在疫情开始时一周内处于最高值,分别为8.37(95%CI:6.62~10.41)、7.11(95%CI:5.46~9.06)、9.29(95%CI:7.1~11.88),后持续处于下降趋势。深圳市R0(t)于1月31日达到最高,为5.85(95%CI:4.98~6.81),而后逐渐下降。4个城市R0(t)均在2月3日-2月9日下降至1,随后维持在1以下。结论截至2020年2月25日,4个一线城市疫情已得到有效控制。复工复学人员的流动可能对疫情的走势有一定的影响,一线城市应注意防范境外疫情输入风险。

Objective To analyze the epidemic status of COVID-19,and its prevention and control in Beijing,Shanghai,Guangzhou and Shenzhen,and provide scientific evidence for COVID-19 prevention and control.Methods Based on publicly available data from the website of National Health Commission of the People’s Republic of China,a mature model was used to estimate the dynamic change of R0 at different time points(R0[t]),so as to evaluate the trend of COVID-19 infectivity over time under the existing prevent measures.Results As of 24:00 on February 25,400,336,346,and 417 patients with COVID-19 were diagnosed in Beijing,Shanghai,Guangzhou,and Shenzhen,respectively.The four cities had the highest single-day diagnosis from January 30 to February 2.The number of new cases per day began to decline from February.On February 3 and within 3-5 days after February 10,the daily increase in the number of new cases in each of the four cities showed a brief upward trend.R0(t)in Beijing,Shanghai and Guangzhou was at the highest value within one week at the beginning of the outbreak,which was 8.37(95%CI:6.62-10.41),7.11(95%CI:5.46-9.06),9.29(95%CI:7.1-11.88),respectively,and then continued to decline.R0(t)in Shenzhen reached its highest value on January 31,at 5.85(95%CI:4.98-6.81),and then declined gradually.The R0(t)of the four cities all dropped to 1 on the 21st day(February 10)of the outbreak,and remained below 1.Conclusion As of February 25,the epidemic situation in four first-tier cities is currently under effective control.The movement of returning to work and study may have an impact on the epidemic situation.Besides,first-tier cities should pay attention to the risk of overseas epidemic import.