The coronavirus disease 2019 (COVID-19) pandemic is changing and impacting lives on a global scale. In this talk, I will introduce a mean-field game model for controlling the propagation of epidemics in a spatial domain. The control variable, the spatial velocity, is first introduced for the classical disease models, such as the Suspected-infected-recovered model. We provide fast numerical algorithms based on proximal primal-dual methods for this proposed model. Numerical experiments demonstrate that the proposed model illustrates how to separate infected patients in a spatial domain effectively. This talk is based on joint work with Wonjun Lee, Wuchen Li, Hamidou Tembine, and Stanley Osher.