Mathematical assessment of co-dynamics of deformed wing virus variants A and B infections in honeybees

This study presents a mathematical model to assess the co-dynamics of infections with Deformed Wing Virus (DWV) Variants A and B within a honeybee hive. The model is analyzed via submodels, DWV A only and DWV B only. Our qualitative analysis results demonstrate that the disease-free equilibrium of each submodel is locally asymptotically stable when the corresponding reproduction number is below one. In addition, the submodels exhibit backward bifurcation. A numerical simulation shows that breeding bees for resistance reduces the number of infected brood and adults. The simulation further suggests that enhancing the efficiency of breeding bees for hygienic and grooming behavior in bees could be an effective strategy for controlling the spread of both DWV variants and mite populations. The sensitivity analysis results show that the most important parameters that contribute to the generation of more DWV infections are the transmission rate of DWV-B, the rate of maturation to infected adult bees, and the egg-laying rate. Furthermore, the uncertainty analysis result highlights that focusing on interventions like breeding bees for resistance, hygienic, and grooming behavior could lead to a relatively lower reproduction number. Finally, the result obtained from cost-effectiveness analysis suggests that implementing all interventions concurrently (the universal strategy) is the most cost-effective when resources are available. Otherwise, breeding bees for hygiene and grooming behavior is the most cost-effective strategy. However, the choice of which strategy to implement depends on policymakers’ budget constraints.