Insect repellent appears to repel mosquitoes by confusing them
The insect repellent DEET doesn’t actually repel insects — it confuses them. New research suggests that DEET gums up sniffing machinery, sabotaging an insect’s sense of smell.
Nerve cells that send odor-related signals to the brain respond differently to DEET if it’s sniffed alone or with other scents, experiments with fruit flies reveal. DEET’s effects also vary depending on what variety of smell-receiving machinery catches the scent, and whether it’s a whopping dose or just a whiff, a team of researchers reports online September 21 in Nature.
“The effects of DEET are not straightforward,” says neuroscientist Maurizio Pellegrino of the University of California, Berkeley, a member of the research team. “We think it confuses the odor coding — the insect doesn’t know exactly what it is smelling.”
While the highly effective compound has been protecting people for decades from loa