Bugged no More

DEET has been the most widely recommended insect repellent for the past 50 years. But mosquitoes are fast becoming immune to it. Previous studies have found mosquitoes with a genetic mutation that made them immune to DEET but what is being seen now is different. It has been found that even the mosquitoes that are initially sensitive to the chemical are able to ignore its smell within a few hours of exposure. This might be happening because the insects’ antennae became less chemically sensitive to DEET over time, just like people get used to smells they experience for long. 

Source

Down To Earth, March, 2013