Research on simulation model of virus transmission in border areas based on two-region contact network

The SARS-CoV-2 virus, due to its high transmissibility and potential severity, has remained a major global public health concern. With the acceleration of globalization and the increasing frequency of human mobility, the risk of viral transmission—particularly cross-border spread—has grown significantly, with border regions becoming critical zones for epidemic dissemination due to their complex and dynamic characteristics. Existing contact network-based models of virus transmission have primarily focused on single-country or localized settings, often failing to adequately capture multi-regional dynamics or the heterogeneity of intervention policies arising from national differences. To address these limitations, this study proposes a multi-regional scale-free contact network simulation model, representing different countries or regions as distinct network layers. Intensive intra-regional contacts are modeled within each layer, while cross-regional transmission occurs through limited individual mobility. The model allows for region-specific implementation of heterogeneous intervention strategies and incorporates the actual epidemic progression in Ruili City to design a context-specific, dynamically adjusted policy combination that effectively achieves dynamic clearance of infections. Furthermore, the model simulates scenarios involving unauthorized cross-border entries, demonstrating that the proposed strategy maintains strong control performance against imported infections under such high-risk conditions.