Résumé
Background : The search for new ways to control mosquito-borne diseases constitutes a major public health challenge due to the emergence and spread of resistance to insecticides. Natural products, usually secondary metabolites produced by bacteria, plants, or fungi, offer promising alternatives to synthetic insecticidal compounds. In this study, we explored the potential of caffeine, an alkaloid of the methylxanthine family, commonly present in many plants and known for its psychotropic stimulant and toxic effects, as an eco-friendly alternative to conventional insecticides.Methods : We exposed adult mosquitoes to a diet of caffeine dissolved in a 10% sucrose solution at concentrations varying from 128 to 1024 ppm (in the case of Aedes aegypti), or from 50 to 400 ppm (in the case of Anopheles arabiensis and An. gambiae) and followed their survival for up to a month.Results : A significant negative correlation between caffeine dose and mosquito longevity was found in both Anopheles and Aedes (log-rank test P< 0.0001 in all cases). The addition of caffeine did not impact feeding rates on the treated sucrose solution compared to the control.Significance : These results reveal that caffeine is a potential target for mosquito control research aiming at sustainable intervention tools. Its sub-lethal, dose-dependent, cumulative effects on longevity during the course of the mosquito lifespan could help prevent the transmission of pathogens and mitigate the appearance of genetic resistance. Consequently, caffeine represents a promising natural alternative to synthetic insecticides, aiming to reduce the vectorial capacity of mosquito populations without their elimination.