Coevolution of epidemic spreading with actions and opinions in multilayer networks

Epidemic spreading is influenced by human decision-making processes, where individuals simultaneously adjust observable actions and private opinions under social norms. To capture how social norms affect disease transmission, we propose a coevolutionary model on a three-layer network consisting of an epidemic-spreading layer, an action-shifting layer, and an opinion-forming layer, where a Susceptible-Infected-Susceptible (SIS) process evolves depending on individual actions and simultaneously reshapes opinions, with the action-shifting dynamics intrinsically coupled with opinion formation through mechanisms such as cognitive dissonance and attitude–behavior consistency. The convergence and stability of the coupled dynamics are established, showing that the system asymptotically converges to equilibrium, where binary actions approach a Nash equilibrium and continuous opinions converge to their corresponding steady states. Analytical conditions and numerical experiments further indicate that reducing the discrepancy between individuals’ expressed actions and private opinions can help mitigate epidemic spreading.