The power of Catnip
Jacob Sturgess discusses the news that catnip might prove a valuable insect repellent
BZZZ. BZZ. BZZZZZ.
You know the sound. Midges, mosquitoes, quite frankly anything that flies. If something comes at you, it’s asking for trouble and you may well slap it into next week.
If you’re smart, the next time you go near infested waters in mosquito season, you’ll take a handy can of insect repellent to ward them off. But there could be an alternative that is just as effective and often available in the local corner shop, should you be caught in a pinch. Catnip.
The mechanism by which this sweet, feline treat is quite so effective against our buzzy friends has recently been uncovered by researchers in Northwestern University. Usually, modern insect repellents such as DEET work by targeting mosquito odour receptors, rendering them unable to detect the chemical cues that signal the presence of a human. However, the active ingredient of catnip, nepetalactone, was found to trigger an abundant pain receptor TRPA1. This means a quick whiff will actively irritate and repel the mosquito, rather than solely confusing it by masking the scent of prey.
The active ingredient of catnip [triggers] an abundant pain receptor TRPA1
Humans and some other animals have a similar irritant receptor. Our protein is best known as the ‘wasabi receptor’ and you will understand its role in sensing environmental pain if you’ve ever accidently mistaken wasabi for guacamole. The agony. But, because catnip selectively targets the insect receptor, humans are indifferent to its effects, making it a seriously promising repellent. Plants have been able to protect themselves from insects for a long time, so their compounds present an exciting new avenue for repellents and these can often be produced at low costs.
Humans are indifferent to its effects, making it a serious promising repellent
Mosquitos, particularly those acting as disease vectors, present an increasing risk to human health with climate change providing attractive conditions for their travel pole-wards from the equator. But, if you don’t mind the occasional tabby at your ankles, catnip may be the solution.