Overview
- Researchers reported on May 28, 2026 that lab experiments in the Journal of Experimental Biology showed yellow fever mosquitoes (Aedes aegypti) can be trained to associate the smell of DEET with a food reward.
- Scientists used Pavlovian-style conditioning in small groups, pairing DEET odor with blood or sugar, and more than 60 percent of trained mosquitoes later attempted to bite when exposed only to the scent.
- The team and outside experts say the insects appear to detect DEET by smell and also sense chemicals by contact through their legs, which in the experiments limited landing on treated skin.
- Authors and commentators stress the work was done under tightly controlled lab conditions and that DEET remains effective when used as directed, with regular reapplication recommended to avoid low-concentration exposures.
- Because Aedes aegypti spreads dengue, Zika and other diseases, researchers call for field studies to test whether learned attraction to DEET occurs in real-world settings and to inform guidance on repellent use and other bite-prevention measures.