According to a new study, some mosquitoes, just a few hours after their first exposure to the insect repellent DEET, are able to ignore it and are no longer repelled by it. The observed mosquitoes seem to be able to ignore the chemical's noxious smell. This comes from a new study
published in the journal PLOS One.
For the study, scientists looked at the
Aedes aegypti mosquitoes. This species spreads the parasitic diseases dengue and malaria.
DEET (N,N-Diethyl-m-toluamide) is a slightly yellow oil. It is the most common active ingredient in insect repellents. It is intended to be applied to the skin or to clothing, and provides protection against tick bites, mosquito bites, chiggers, and other insects that can transmit disease. The chemical was developed by the United States military to protect troops undertaking jungle warfare during World War II.
To understand the diminished effects of the chemical, as the
BBC has reported, researchers based at the London School of Hygiene and Tropical Medicine attached electrodes to the antennas of female mosquitoes as the insects sought to feed on a human arm covered in DEET. Three hours after the chemical repelled the mosquitoes, some returning insects were less sensitive to the unpleasant smell.
According to the
Daily Telegraph, upon examination, the resistance was linked to a lower response in the neurons in the mosquitoes olfactory receptor (which provides the 'sense of smell').