Interactive effects of climate change and human mobility on dengue transmission

The global escalation of vector-borne epidemics, particularly flaviviruses like dengue fever, presents a growing challenge. Contributing factors such as climate change and increased human mobility have expanded the vulnerability to dengue fever worldwide, yet the underlying mechanisms remain elusive. In this paper, we extend a two-patch dengue transmission model by incorporating the aquatic stage of mosquitoes and integrating the movement of host individuals between patches via a residence-time matrix. Through this approach, we derive the basic reproduction number and directly link it to climate change and human mobility. Our findings reveal bidirectional impacts of human mobility on dengue transmission: an increase in mobility from climatically unsuitable to suitable patches heightens the basic reproduction number, while the reverse pattern diminishes it. Moreover, an asymmetric mobility rate proves potentially more conducive to dengue spread than a symmetric pattern. When coupled with climate changes, asymmetric human mobility further exacerbates dengue fever transmission. These insights offer novel perspectives on the role of human mobility in dengue transmission dynamics and inform intervention strategies, particularly in urban settings where dengue epidemics are driven by human mobility.