Some mosquitoes not bothered by repellent DEET

By Tom Nordlie • Published: July 23rd, 2010
Category: Health in a Heartbeat

The battle between humans and bugs has been going on for centuries and shows no sign of stopping.

It works like this:

People find ways to make pest insects less problematic, then some of the insects get around the control measures.

Case in point: the mosquito repellent DEET.

This chemical has been around more than sixty years.

Developed by the U-S Army, it’s the yardstick used to judge all other concoctions meant to beat the bloodsuckers.

For reasons unknown, mosquitoes hate the smell of DEET. Well, most of them.

A small percentage isn’t deterred by DEET.

A study published in the journal Proceedings of the National Academy of Sciences sheds light on this phenomenon.

It shows that some mosquitoes are genetically insensitive to the repellent.

Researchers began by caging female mosquitoes from a well-known biting species. They offered the mosquitoes a human arm treated with DEET.

About thirteen percent weren’t bothered by the repellent. They were selected out, then bred with males of unknown sensitivity.

After several generations of breeding, the percentage of DEET-resistant mosquitoes topped fifty percent.

The scientists concluded that insensitivity is an inherited trait.

What does that mean to people who’d like to enjoy some bite-free fun around the barbecue grill?

They need to employ a multipronged strategy.

Besides using DEET-based products, options include staying indoors around dusk and wearing clothes that limit their access to bare skin.

Also, eliminate sources of standing water, to thwart mosquito breeding.

Chances are, the human race will never completely outwit mosquitoes.

But we can make it a good fight.

All it takes is a little ingenuity. And some swatting.