A control strategy for Sterile Insect Techniques using exponentially decreasing releases to avoid the hair-trigger effect

Abstract

In this paper, we introduce a control strategy for applying the Sterile Insect Technique (SIT) to eliminate the population of Aedes mosquitoes which are the vectors of various deadly diseases like dengue, zika, chikungunya... in a wide area. We use a system of reaction-diffusion equations to model the mosquito population and study the effect of releasing sterile males. Due to the so-called hair-trigger effects, the introduction of only a few individuals can lead to the invasion of mosquitoes in the whole region after some time. To avoid this phenomenon, our strategy is to keep releasing a small number of sterile males in the treated zone and move this release forward to push back the invasive front of wild mosquitoes. By proving a comparison principle for the system and using the traveling wave analysis, we show in the present paper that the strategy succeeds with a finite amount of sterile male mosquitoes. We also provide some numerical illustrations for our results.