"Mosquito-borne pathogens is one of the significant sources of human mortality and morbidity around the world, in particular dengue fever whose principal vectors are the mosquitoes Aedes aegypti (Linnaeus) and Aedes albopictus (Skuse). A new method of vector control takes advantage of sugar feeding by mosquitoes and involves toxins incorporated into sugar meals presented in bait formulations. Spinosyns comprise a family of bacterial secondary metabolites with a unique mode of action against the insect nervous system, an appealing environmental safety profile, and potential for incorporation in sugar baits. This research evaluated acute and subacute toxicity of spinosad and spinetoram (combinations of certain spinosyns and derivates) in sugar solution as an oral toxin against adult Ae. aegypti and Ae. albopictus. Spinosad and spinetoram delivered in sugar solution were toxic to males and females in bioassays. Toxicity as measured by an acute exposure doubled from 24 to 48 hours of assessment, revealing a relatively slow action. Spinetoram tended to be more acutely toxic than spinosad. Subacute exposure to these products in sugar solution the exposure significantly reduced the survivorship of males and females of Ae. aegypti and Ae. albopictus as revealed by longitudinal Kaplan-Meier analysis. Fecundity was not significantly affected for Ae. aegypti but was higher in exposed compared to nonexposed females, whereas it significantly increased for Ae. albopictus, possibly due to a hormesis effect. Fertility, on the other hand, was significantly iii reduced following the exposure to either spinosad or spinetoram in sugar solution for both Aedes species, suggesting in vivo toxicity to eggs in those females surviving subacute exposures."--Pages ii-iii.
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