Modelling of COVID-19 Transmission in the Regional Municipality of Durham, Ontario

目前使用的COVID-19流行病学模型是在大流行的初期阶段开发的，是大规模模型，提供了整个国家或整个省份的暴露、感染和康复/死亡个体的数量（按年龄和/或合并症分层）。 这些模式在大流行病的初期阶段是足够的，当时的优先事项是不惜一切代价减缓感染速度和减少感染人数，包括使用严格的身体距离措施。 当我们进入第二阶段时，目标是尽可能多地重新启动经济活动，同时避免第二次感染高峰，因为第二次感染高峰可能会使急诊室和整个医疗机构不堪重负，并导致经济再次放缓。 现在已经很明显的是，第二阶段将需要采取更加细致的办法，这将在很大程度上取决于当地的具体条件。 这项研究将： 1)制定一个详细的，多隔间动态流行病学模型，具体到达勒姆，安大略地区市，并实施它作为一个软件包部署在达勒姆地区卫生部。 2)开发室内环境的小规模实验模型，用于研究液滴扩散，并使用研究结果为安大略达勒姆地区的特定企业和活动制定物理距离和保护措施的建议。

COVID-19 epidemiological models in current use were developed during the beginning stages of the pandemic and are large-scale models which provide numbers of exposed, infected, and recovered/deceased individuals (stratified by age and/or comorbidities) for the entire country or for an entire province. Those models were adequate in the initial stages of the pandemic, when the priority was to slow down the rate of infection and reduce the number of infected individuals at all costs, including the use of stringent physical-distancing measures. As we move to the second phase, the objective is to restart as much of the economic activity as possible, while avoiding a second peak in infections which can potentially overwhelm emergency departments and health-care facilities in general, as well as lead to renewed economic slowdown. It has now become evident that this second phase will require a much more nuanced approach, which will depend greatly on specific local conditions. This research will: 1) Develop a detailed, multi-compartment dynamic epidemiological model specific to the Regional Municipality of Durham, Ontario, and implement it as a software package to be deployed in the Durham-Region Health Department. 2) Develop reduced-scale experimental models of indoor environments for the study of droplet dispersion and use study findings to develop recommendations for physical distancing and protective measures for specific businesses and activities in Durham Region, Ontario.