Numerical Simulation, Sensitivity Analysis, and Intervention Strategies for Zika Virus Epidemic Control Using a SEIVTR Compartmental Model

Abstract

Mathematical models of infectious disease attain their greatest public health utility when rigorously established analytical properties are translated into scenario-specific numerical predictions that can directly guide outbreak response and policy design. This study presents comprehensive numerical simulations and sensitivity analyses of a SEIVTR (Susceptible– Exposed–Infected–Victim–Treatment–Recovered) deterministic model for Zika virus transmission, whose analytical foundations, including a derived basic reproduction number of R₀ ≈ 2.37, are established in a companion analytical study. Using the MATLAB ODE45 numerical solver, we simulate the temporal dynamics of all six epidemiological compartments across multiple scenarios reflecting different combinations of compartmental classes. Key findings include the rapid depletion of the susceptible population within three days of outbreak initiation, peak exposure and infection at days five to seven, a treatment-class burden peaking around days three to four, and accumulation of recovered individuals by day 20. Sensitivity analysis identifies the mosquito biting rate (β) and vector mortality rate (γ) as the dominant drivers of R₀ variability, together accounting for approximately 60% of peak infection variance, while sexual transmission (δ), though secondary, significantly prolongs the epidemic tail by approximately three days. Scenario-based intervention analysis demonstrates that a combined strategy comprising a 50% reduction in the mosquito biting rate, 75% treatment efficacy, and a 60% reduction in sexual transmission can reduce R₀ below unity and lower cumulative case burden by up to 45%. The potential for backward bifurcation under near-threshold conditions underscores the need for sustained, rather than intermittent, multi-layered control. These findings generate actionable public health recommendations for synchronised vector management campaigns, rapid diagnosis-to-treatment protocols, and behavioural sexual health interventions as the critical pillars of an integrated Zika virus epidemic response strategy.