title: Aedes aegypti mosquitoes exhibit decreased repellency by DEET following previous exposure.
abstract: DEET (N,N-Diethyl-m-toluamide) is one of the most widely used mosquito repellents. Although DEET has been shown to be extremely effective, recent studies have revealed that certain individual insects are unaffected by its presence. A genetic basis for this has been shown in Aedes aegypti mosquitoes and the fruit fly Drosophila melanogaster, but, for the triatomine bug, Rhodnius prolixus, a decrease in response to DEET occurred shortly after previous exposure, indicating that non-genetic factors may also be involved in DEET "insensitivity". In this study, we examined host-seeking behaviour and electrophysiological responses of A. aegypti after pre-exposure to DEET. We found that three hours after pre-exposure the mosquitoes showed behavioural insensitivity, and electroantennography revealed this correlated with the olfactory receptor neurons responding less to DEET. The change in behaviour as a result of pre-exposure to DEET has implications for the use of repellents and the ability of mosquitoes to overcome them.
authors: Biological Chemistry and Crop Protection Department, Rothamsted Research, Harpenden, Hertfordshire, United Kingdom.
authors: Nina M
authors: NM
authors: Stanczyk
authors: John F Y
authors: JF
authors: Brookfield
authors: Linda M
authors: LM
authors: Field
authors: James G
authors: JG
authors: Logan
mesh_terms: D000330:Aedes / Q000187:drug effects*; D000818:Animals; D001132:Arm; D057506:Arthropod Antennae / Q000187:drug effects / Q000502:physiology; D001522:Behavior, Animal / Q000187:drug effects; D003671:DEET / Q000633:toxicity*; D004781:Environmental Exposure; D005260:Female; D006801:Humans; D007302:Insect Repellents / Q000633:toxicity*; D007305:Insecticide Resistance / Q000187:drug effects*; D012903:Smell / Q000187:drug effects
chemical_list: D007302:Insect Repellents; D003671:DEET