Rural revitalization, carbon emissions, and infectious disease transmission in China: nonlinear dynamics, spatial spillovers, and moderating effect.

Atmospheric pollution, particularly carbon dioxide (CO2) emissions driven by rapid economic development, poses significant threats to public health. In China, rural revitalization policies have transformed rural environments and socioeconomic structures, with implications for infectious disease transmission. This study examines the relationship between carbon emissions, rural revitalization, and infectious diseases using panel data from 31 provinces (2013-2023) within a spatial econometric framework. Results show that carbon emissions significantly increase disease transmission. Rural Revitalization exhibits a significant U-shaped non-linear effect, shifting from an initial negative impact that suppresses infection risks to a subsequent positive impact that elevates risks driven by enhanced population mobility and economic integration. Spatial Durbin Model reveals profound positive spatial spillover effects, demonstrating that both Carbon Emissions and Infectious Disease Transmission are highly interdependent across neighboring provinces. This indicates that a region's epidemiological risk is heavily conditioned by the transboundary environmental pressures and developmental trajectories of its contiguous territories. These findings underscore that coordinating environmental and rural development policies through a transition toward stage-dependent, low-carbon rural planning and cross-regional collaborative governance is a vital prerequisite for mitigating public health expenditures and safeguarding long-term regional sustainability.