Simulation analysis of the coronavirus disease 2019(COVID-19) spread based on system dynamics model

The outbreak of public health emergencies not only threatens people's life safety, but also has a series of secondary effects. In this paper, based on SEIR classical infectious disease model, covid-19 epidemic model is constructed by using system dynamics method.Based on different isolation measures and protection measures in different regions, the model was simulated to dynamically describe the change rule of epidemic infection number with time. The results show that the earlier the government takes isolation measures, the more active people will protect themselves, which can effectively reduce the number of infected people and control the epidemic situation faster .