Evolving Social Context Regulates Contagion Spread in Multiplex Networks

Contagion processes across biological, behavioral, and informational systems are shaped not only by transmission dynamics, but also by adaptive social responses emerging through human interactions. Understanding how social context regulates contagion spread is therefore critical for characterizing real-world spreading processes. Yet standard epidemic models often focus primarily on contagion states, treating social context as static or only weakly coupled to transmission. Here, we develop a multiplex-network framework that couples contagion dynamics with co-evolving social context. Unlike classical threshold contagion models, which apply thresholds directly to contagion prevalence or adoption states, our framework applies heterogeneous local and global thresholds to evolving context dynamics. The model further captures context-mediated transmission through targeted spread, in which contagion selectively propagates toward the locally most context-vulnerable susceptible individual. This contrasts with broadcast transmission, where spreading effort is distributed uniformly across susceptible neighbors. We show that coupling contagion with evolving context fundamentally reshapes spreading dynamics, producing delayed convergence and non-monotonic final prevalence. Targeted and broadcast transmission mechanisms exhibit distinct sensitivities to local and global social responses, highlighting tradeoffs in intervention strategies. We further show that co-evolving context can generate resilience by slowing propagation and delaying equilibrium, while pre-existing social resilience can substantially suppress contagion even under high transmission rates. These results suggest that contagion outcomes can vary substantially as a function of evolving social response and pre-existing social resilience.