Temperature and Competition: Drivers in the Ecological Dynamics of Aedes Mosquitoes and Dengue Spread

Dengue, a mosquito-borne viral disease common in tropical areas, is spread by Aedes aegypti and Aedes albopictus. Temperature changes driven by climate affect vector ecology and expand regions of species coexistence. The combined effect of temperature and larval competition on mosquito dynamics and dengue transmission is unclear. We built a deterministic model with temperature-dependent parameters to study larval-stage interactions, linked with a SEIR framework for human infection. We assessed invasion potential, coexistence, and infection peaks. The basic reproduction number (R0) was calculated using the Next Generation Matrix, and the effective reproduction number (Rt) came from simulations with larval competition. Aedes albopictus invades aegypti-dominated systems when the aegypti competition coefficient is below 0.47, with neutral equilibrium from 0.47 to 0.60 and exclusion above 0.60 in stable conditions. In temperature-dependent settings, invasion extends to a coefficient of 0.75. Coexistence analysis showed aegypti dominance (~87% abundance) in stable settings, while temperature-dependent conditions led to ~50% abundance for both species. Dengue cases peaked at 156-168 in stable conditions and 195-220 in temperature-dependent ones. Stronger albopictus competition lowered peaks in both cases. Temperature boosts albopictus invasion and coexistence, while aegypti drives higher infection peaks. Balanced species abundances raise transmission risks, emphasizing the need to factor temperature and competition into vector control.