1.Department of Respiratory and Critical Care Medicine, the first Affiliated Hospital of Nanjing Medical University;2.Department of Respiratory and Critical Care Medicine, Shuyang Hospital of Traditional Chinese Medicine, Jiangsu Province
目的：分析江苏省由SARS-CoV-2 Omicron变异株引起的新型冠状病毒肺炎（coronavirus disease 2019，COVID-19）的流行病学特征，为后续疫情的防控措施提供数据支持。方法：收集江苏省卫生健康委员会官网以及各市政府官方通报（2022年2月13日至2022年4月9日）的新型冠状病毒肺炎病例数据并进行流行病学调查研究。结果：截至2022年4月9日，江苏省SARS-CoV-2 Omicron变异株引起的COVID-19疫情蔓延势头目前初步遏制，累积发病率为0.48/10万，病死率为0。总体呈现无症状感染者比例高（76.3%），确诊病例中以轻型为主的特点。发病中位年龄为42岁，＜20岁感染者占16.9%。Omicron BA.1变异株中位潜伏期为5.0（4.5,6.0）d，BA.2变异株中位潜伏期为3.0（2.8,3.5）d，两组潜伏期差异有统计学意义（P＜0.05）。聚集性病例比例较高（81.6%），主要来自家庭聚集。结论：Omicron变异株传染性强，潜伏期短，毒力减弱，本阶段江苏省Omicron感染病死率为0，江苏省实施的精准防控成果显著。
Objective：To analyze the epidemiological characteristics of coronavirus disease 2019 caused by SARS-CoV-2 Omicron variant and provide data support for prevention and control measures followed. Methods：The COVID-19 data during February 13,2022 to April 9,2022 were obtained from official website of Jiangsu province Health Commission and municipal governments. Descriptive epidemiological methods were used to analyze the characteristics of cases. Results：As of April 9, 2022, the spread of COVID-19 caused by SARS-CoV-2 Omicron variant in Jiangsu province has been initially contained, with a cumulative incidence of 0.48/100,000 and a fatality rate of 0. It was characterized by a high proportion (76.3%) of asymptomatic patients, and most of the confirmed cases were mild. The median age was 42 years. 16.9% infected individuals were under 20 years old. The median incubation period of Omicron BA.1 variant was 5.0 (4.5,6.0) days, and that of BA.2 variant was 3.0 (2.8,3.5) days, with significant difference (P＜0.05). There was a high proportion of cluster cases (81.6%). Among them, the main type was family cluster. Conclusion：Omicron variant is highly infectious, with short incubation period and weakened virulence. At this stage, the fatality rate of infection caused by Omicron variant in Jiangsu province was 0. The results of precise epidemic control measures implemented in Jiangsu Province were remarkable.