Since the outbreak of COVID-19 pandemic, many countries have experienced the multiple outbreaks of infection, accompanied by lockdown, opening and re-lockdown and re-opening and etc. It is challenging to identify economic strategies for simultaneously relaxing the countermeasures and containing the pandemic. In this talk I initially summarize what we have done on the prediction of COVID-19 pandemic and effect of massive movement on the possible outbreak. I then present our recent work on COVID-19 infection, including a multi-scale models describing the multiple outbreaks and optimal strategies to coordinate disease control, social distancing and the cost. Finally I shall give some considerations and thoughts on modelling COVID-19 infections and concluding remarks.

Bio: Dr. Yanni Xiao, a full professor in the School of Mathematics & Statistics at Xi'an Jiaotong University, Xi’an, China, the director of the Interdisciplinary Research Center of Mathematics and Life Sciences. Dr Xiao has colloborated with China CDC on modeling HIV/AIDS infection as a PI of the subproject of National Mega-project of Science Research. She has served as PI for several NSFC grants including a key program. Her research focuses on modeling the infectious disease at multi-scale levels, predicting and assessing the efficacy of interventions, and providing the basis for decision-makers.