Government response, individual decision-making, and disease spreading: Insights from a game-epidemic dynamics model

During pandemic events, prompt government responses play an indispensable role in controlling the infection situation. Individual decision-making about whether to support government control is crucial for the thorough and effective implementation of policies. To characterise this mechanism, we construct a networked SIR model that introduces an evolutionary game framework. Behavioural effects that significantly influence disease dynamics within the coupled disease-behaviour system are captured through sensitivity analysis. Our results show that the heterogeneity of individual contact is also strongly reflected in their decision-making mechanisms. Groups with larger degrees are more sensitive to changes in the government response strength, while conversely, those with smaller degrees are more likely to be affected by the ratio between the costs of the two strategies. Irrational decision-making by individuals is identified as a central driver in inducing the recurrence of multiple waves of outbreaks. In addition, taking the social dilemma phenomenon as an entry point, we prove from a game-theoretic perspective that individuals with greater degrees in heterogeneous populations have more possibility for interest conflicts with the government and are potential crisis makers during an epidemic. The interaction between government response, individual decision-making, and disease transmission is more comprehensively revealed through our study. Our results are expected to provide theoretical support for public health policymaking in the future.