Best Ways to Repel Insects

Mosquitoes, gnats and other insect annoyances have been bugging mankind for millennia. Here's how to fight back.

The war against mosquitoes is deadly serious business when it comes to infectious diseases like malaria and the West Nile virus. But mosquitoes and other biting insects are also perennial irritants at Memorial Day parties, backyard barbecues, and other summer celebrations. Here are some of the ways we use modern science and technology to get the little pests to bug off.

Chemical repellents are still the most common and effective way to reduce mosquito bites. They repel by essentially disrupting the sensory system of the female mosquito (only the ladies bite). Several retail bug repellents use compounds derived from the oil of the eucalyptus tree, also a favorite of koala bears. Plant-derived repellents are generally regarded as safer than synthetic chemical repellents, and comparably effective.

By far the most common synthetic chemical repellent is N,N-diethyl-3-methylbenzamide, also know as DEET, which has been proven effective against mosquitoes, fleas, chiggers and ticks. DEET is used by more than 50 million Americans annually.

A promising new weapon in the war against mosquitoes, the compound known as VUAA1 works by completely overloading the female mosquito's sense of smell. Instead of blocking certain olfactory systems, VUAA1 basically activates all the mosquito's receptors, thereby scrambling her evil little head. Discovered in 2011, the compound is not yet commercially available but is believed to be thousands of times more effective than DEET.

Electric bug zappers have been around a lot longer than you might think -- the first was patented back in 1934. Commercially, they're very successful and have even spawned handheld variants like The Executioner. But scientifically speaking, they're not so hot. Studies show that, on average, only a tiny percentage of bugs killed by the average backyard zapper are pests. Meanwhile, billions of harmless or even beneficial insects are killed by zappers each summer.

Another gadget that's much more successful on retail shelves than in scientific studies, ultrasonic bug repellent devices purport to sonically disorient flying insects, or scare them away with the sound of other insects or even bats. While individual testimonials abound, scientific studies have shown these devices have little or no effect on hungry bugs.

There are plenty of reasons to like LED light bulbs -- low power consumption, long life, brightness -- but there may be yet another reason to install them on your porch. Insects are attracted to UV light, and most LED lamps emit very little light in that spectrum. There's no conclusive science yet, but anecdotal accounts suggest insects aren't as attracted to LEDs as they are to traditional incandescent bulbs.

In the dog days of summer, it may be that the best insect-repelling technology is a simple electric fan. Mosquitoes are relatively weak fliers, and even a mild breeze will keep them at bay. Fans also disperse the body heat and carbon dioxide emissions that mosquitoes use to sniff us out.