Modelling Cross-border Mobility During Disease Outbreak

Due to the COVID-19 pandemic various cross-border policies such as mandatory testing, quarantining upon arrival, travel restrictions have been implemented by the countries to minimize the risk of disease import. The strictness of these measures has varied over time. The aim of this study is twofold. First, we develop a spatially explicit SIR-type compartmental model to evaluate the impact of cross-border mobility between two countries on the disease dynamics under different epidemic conditions. We see a significant change in the time to reach the peak of infection if the cross-border mobility is permitted during disease outbreak. Moreover, our study shows that allowing cross-border mobility shortens the difference in peak timings in two countries in comparison to the scenario with no cross-border flux. Next, we present a method using stochastic simulation for estimating cross-border mobility flux between two regions from the difference in peak-timing in infection under some reasonable assumptions.