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自新型冠状病毒肺炎(coronavirus disease 2019,COVID-19)疫情发生以来,中国大多数的病例集中在武汉市.虽然早期病例数和死亡人数迅速增加,但通过采取多种防控措施,疫情得以快速遏制.纵观全球,疫情已蔓延至全球六大洲的187个国家,确诊病例数已超过300万,这一数字仍在快速增长.在此特殊背景下,有必要对我国疫情防控措施开展科学的、定量的评估,为全球疫情防控提供决策依据.为此,本研究评估了临床诊断标准实施和全城症状排查对武汉市疫情控制的贡献.考虑COVID-19的传播机理、隔离措施等,建立SEIR+Q传播动力学模型.基于武汉市截至2020年2月14日官方公布的每日确诊病例数和未确诊的临床诊断病例数进行建模,并预测2月14日以后的疫情态势.基于实际疫情数据,与模型预测趋势相比较,评价防控措施效果.结果显示,若维持2月14日以前防控措施不变,那么预测将于3月25日和4月29日,每日新增病例数分别降至100例和10例以下,将于5月31日首次现零.而事实上,截至3月6日,武汉市每日新增病例数降至100例以下,截至3月11日降至10例以下,3月18日首次实现零增长,较之模型预测结果分别提前了19 d、49 d和74 d.截至3月30日,实际累计病例数为50006例,比模型预测值减少19951例.有效再生数[effective reproductive number,R(t)]分析显示,2月6?10日的第一次全城症状排查后,R(t)显现出下降趋势,2月12?14日的临床诊断标准实施和2月17?19日的第二次全城症状排查后,R(t)显现出较大的降幅,与实际情况较为一致.综上所述,武汉市临床诊断标准的实施和全城症状排查等综合防控措施成效显著,可为世界各国的疫情防控决策提供科学依据.“,”The majority of cases infected with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in China centered in the city of Wuhan. Despite a rapid increase in the number of cases and deaths due to the coronavirus disease 2019 (COVID-19), the epidemic was stemmed via a combination of epidemic mitigation and control measures. This study evaluates how the implementation of clinical diagnostics and universal symptom surveys contributed to epidemic control in Wuhan. We extended the susceptibles-exposed-infectious-removed (SEIR) transmission dynamics model by considering three quarantined compartments (SEIR+Q). The SEIR+Q dynamics model was fitted using the daily reported number of confirmed infections and unconfirmed cases by clinical diagnostic criteria up to February 14, 2020, in Wuhan. Applying the model to carry forward the pre-February 14 trend in Wuhan, the num-ber of daily new diagnosed cases would be expected to drop below 100 by March 25, below 10 by April 29, and reach 0 by May 31, 2020. The observed case counts after February 14 demonstrated that the daily new cases fell below 100 by March 6, below 10 by March 11, and reached 0 by March 18, respectively, 19, 49, and 74 d earlier than model predictions. By March 30, the observed number of cumulative confirmed cases was 50006, which was 19951 cases fewer than the predicted count. Effective reproductive number R(t) analysis using observed frequencies showed a remarkable decline after the implementation of clinical diagnostic criteria and universal symptom surveys, which was significantly below the R(t) curve estimated by the model assuming that the pre-February 14 trend was carried forward. In conclusion, the proposed SEIR+Q dynamics model was a good fit for the epidemic data in Wuhan and explained the large increase in the number of infections during February 12–14, 2020. The implementation of clinical diagnostic criteria and universal symptom surveys contributed to a contraction in both the magnitude and the duration of the epidemic in Wuhan.