'Eau de human' repellent aims to deter mosquitos

The new repellent may be potent enough to keep mosquitos away if just applied to clothing. Picture / Reuters

LONDON - Scientists are determined to even the score with mosquitoes by developing bug repellents using chemicals in human body odour that the insects hate.

They have isolated chemicals in the odour of people who don't get bitten and hope to use them to improve controls to prevent the spread of insect-borne diseases such as malaria, dengue and yellow fever in developing countries.

"Those of us who don't get bitten by mosquitoes produce unattractive chemicals, which mask their otherwise attractive odours," said Professor John Pickett of Rothamsted Research, a charitable scientific trust in England.

"It's extra chemicals that they produce. I think these convey some message to the insect that the would-be host is not as suitable as another individual," he added.

Pickett and researchers from Aberdeen University in Scotland used a technique known as gas chromatography-electroantennography to identify which components of the odour mosquitoes can detect.

They are currently comparing their impact to insect repellents approved by the World Health Organisation (WHO).

So far results have been promising, according to the researchers. In addition to mosquitoes, they are also looking at tics and other disease-carrying insects.

"By plugging into something that is such a fundamental part of the insects' ecology, it gives you the opportunity to get something that will be much more potent," said Pickett.

The scientists, who have submitted their findings for publication in a scientific journal, are still working on formulations for the repellent to ensure it lasts for a long time.

They are demonstrating the techniques they used to detect the chemicals at The Royal Society Summer Science Exhibition that opens on Monday.

Because it is such a potent repellent, Pickett said it may not be necessary to apply it to the skin. Putting it on the cuffs of a shirt or trousers may be enough to keep the bugs away.

They hope to develop a formula that will be marketed within about two years.

- REUTERS