School of Engineering Science, University of Chinese Academy of Sciences, Beijing 100049, China.
School of Public Policy and Management, University of Chinese Academy of Sciences, Beijing 100049, China.
Int J Environ Res Public Health. 2022 Sep 19;19(18):11810. doi: 10.3390/ijerph191811810.
The continued severity of the global epidemic situation has led to a rising risk of imported cases in China, and domestic cluster epidemic events caused by imported cases have occurred from time to time, repeatedly causing nation-wide disruption. To deeply explain this phenomenon, this study adopted the grounded theory method, using the 5·21 Guangzhou COVID-19 outbreak and 7·20 Nanjing COVID-19 outbreak as examples to study the risk transmission mechanism of domestic cluster epidemic caused by overseas imported cases. The study found that the risk factors for the phenomenon mainly include the following seven aspects: external protection, operations and supervision, international and domestic environment, contaminated objects, virus characteristics, management efficacy, and individual factors. These risk factors together constitute the "detonator", "risk source", "risk carrier," and "risk amplifier" in the risk transmission process. In addition, this study also found that the transmission mechanism of domestic clusters caused by imported cases is a process of secondary risk amplification. The increase in risk carriers leads to a surge in secondary risks compared with the first, which leads to the outbreak of domestic clusters. Finally, based on the characteristics of the transmission mechanism and risk transmission components, this study provides some suggestions on risk mitigation for public departments to optimize China's epidemic prevention policies.
全球疫情形势持续严峻，导致中国输入病例风险上升，国内由输入病例引发的聚集性疫情时有发生，给全国疫情防控造成了较大压力。为深入阐释这一现象，本研究采用扎根理论方法，以 5·21 广州疫情和 7·20 南京疫情为例，研究境外输入引发国内聚集性疫情的风险传播机制。研究发现，引发该现象的风险因素主要包括境外输入、操作与监管、国际与国内环境、污染物体、病毒特征、管理效能、个体因素这七个方面。这些风险因素共同构成了风险传播过程中的“引爆器”“风险源”“风险载体”“风险放大器”。此外，本研究还发现境外输入引发国内聚集性疫情的传播机制是一个二次风险放大的过程，风险载体的增加导致二次风险相较于首发性风险呈倍数式增长，进而引发国内聚集性疫情的爆发。最后，本研究基于传播机制和风险传播构成的特点，为公共部门提出风险缓解建议，以优化中国的疫情防控政策。
