It's proven: if you spray your body with a mosquito repellent that contains DEET, no insect will dare to bite you. But what does this product, used for half a century, repel mosquitoes?
A team of scientists has just found the answer, according to the journal Proceedings of the National Academy of Sciences (PNAS). "This substance does not mask the smell of the victim, nor does it physically damage the smell of mosquitoes, as previously thought," explains the Californian chemist and entomologist Walter Leal, co-author of the study. "It just happens that mosquitoes smell DEET very unpleasant, " he adds.
To reach this conclusion, Leal and his partner Zain Syed carefully studied the antennae of the insects. And they detected neurons specialized in detecting DEET. "It is amazing that there are nerve cells responsible for identifying a synthetic compound," says Syed, who admits that he repeated the experiment over and over again to verify that there was no error in his conclusions.
The researchers believe the discovery will help keep mosquitoes totally away from humans . The interest in repellants is high, since these insects not only cause annoying bites, but also transmit diseases as serious as the Nile virus, St. Louis encephalitis or malaria .
