Mosquitoes Can Learn to Associate DEET with Food Rewards, Potentially Altering Repellent Effectiveness
New research published in the Journal of Experimental Biology indicates that mosquitoes, specifically Aedes aegypti, can learn to associate DEET with a food reward, potentially diminishing its effectiveness as a repellent under certain conditions. Scientists used classical conditioning, similar to Pavlov's dog experiment, to train over 250 female mosquitoes. When allowed to feed on blood through a membrane while simultaneously exposed to DEET-scented air, mosquitoes learned this association after only four trials. Nearly 60% of these trained mosquitoes subsequently displayed a biting-attempt response when exposed solely to the scent of DEET, even without blood present. In a second phase, trained mosquitoes even preferred to attempt to bite a human arm treated with DEET over an untreated arm. 
