How did international air transport networks influence the spread of COVID-19? A spatial and temporal modeling perspective

The international air transport network is pivotal in the global propagation of emerging infectious diseases. Gaining insights into the nuances of this transmission mechanism can pave the way for more strategic and effective interventions. While previous studies have delved into the subject, an integrated spatial and temporal modeling framework, specifically tailored to distinct phases of COVID-19 and its variants, has yet to be fully explored. This research aims to address this gap by exploring the spatial and temporal impacts of the air transport network on the spread of COVID-19 and its Omicron variant. We introduce an improved effective distance metric to assess the spatial correlation between various distance metrics and the onset of infectious diseases in selected nations. Subsequently, we employ a network-based heterogeneous susceptible-unreported infectious-confirmed-recovered-death (SUCRD) mathematical model to delineate the temporal evolution of infections by country. Our findings underscore the air transport network’s instrumental role in the pandemic’s spatial dynamics. Moreover, our model has been validated, demonstrating robustness and reliability. Through rigorous validation and simulation experiments, we discern the significance of the timing and intensity of interventions in shaping the pandemic’s trajectory. Notably, while the air transport network exerts a profound influence during the phases of both COVID-19 and Omicron, international travel restrictions exhibit diminishing returns once the disease achieves widespread prevalence. Through comparative analysis and discussion, we highlight the advantages of our experimental outcomes and methodological approach compared to previous studies. Based on our findings, we identify six key policy implications that offer critical perspectives for aviation stakeholders. This study illuminates the role of the air transport network in affecting the spatial accessibility and temporal dynamics of pandemic transmission, thereby providing valuable insights for informed policy-making in the aviation sector.