Impact of quarantine policies on port network performance and robustness during pandemics: a simulation-based analysis

To contain the spread of the virus at ports, many countries have implemented quarantine policies for vessels from abroad during COVID-19. In response, vessels chose to skip the port to save time or undergo a 14-day quarantine to ensure critical supplies, both of which significantly affected the performance of the port network. However, due to the combined effect of many factors, data analysis techniques can hardly identify the impact of quarantine policies on the outcomes. Therefore, to enable both networkwide performance assessment and detailed evaluation for individual vessels and ports under such an unprecedented policy, a microscopic simulation model for the global port network (GPN) is desired. The proposed simulation method is based on real-world vessel movement data from Automatic Identification Systems (AIS) combined with a port database. It is found that the effect of the quarantine policy on a particular port consists of two parts, i.e. the direct impact caused by vessels’ port skipping and the indirect impact caused by network interaction, which is further determined by the location of, and the policy implemented by the port. Furthermore, the ability of the global port network to maintain its performance under different levels of pandemic situations and different rates for vessels to skip the ports requiring quarantine is investigated. Interestingly, in most cases, a moderate port skipping rate (mostly between 20% and 50%) could help improve network performance. The results and presented simulation method can assist policymakers in coping with COVID-19 and potential global catastrophes.