Biopesticides improve efficiency of the sterile insect technique for controlling mosquito-driven dengue epidemics

David R J Pleydell,Jérémy Bouyer

doi:10.1038/s42003-019-0451-1

Abstract

Various mosquito control methods use factory raised males to suppress vector densities. But the efficiency of these methods is currently insufficient to prevent epidemics of arbovirus diseases such as dengue, chikungunya or Zika. Suggestions that the sterile insect technique (SIT) could be “boosted” by applying biopesticides to sterile males remain unquantified. Here, we assess mathematically the gains to SIT for Aedes control of either: boosting with the pupicide pyriproxifen (BSIT); or, contaminating mosquitoes at auto-dissemination stations. Thresholds in sterile male release rate and competitiveness are identified, above which mosquitoes are eliminated asymptotically. Boosting reduces these thresholds and aids population destabilisation, even at sub-threshold release rates. No equivalent bifurcation exists in the auto-dissemination sub-model. Analysis suggests that BSIT can reduce by over 95% the total release required to circumvent dengue epidemics compared to SIT. We conclude, BSIT provides a powerful new tool for the integrated management of mosquito borne diseases.

Highlights

Various mosquito control methods use factory raised males to suppress vector densities
The auto-dissemination technique (ADT) uses mosquitoes to deposit biopesticides at larval sites—providing efficient treatment of the small, hidden and disseminated water bodies Aedes use as larval habitat[11]
Insect control primarily depends on insecticides, with major impacts on human/animal health and food safety[58]

Summary

Results

With SIT, augmenting the daily release rate (R) decreases the asymptotic population density (stable equilibrium) (Fig. 1a, Supplementary Fig. 2A). Unlike SIT, for BSIT the elimination time asymptote shifts to some R

Discussion

Methods

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