Apparently, researchers have isolated the
natural repellent which is found in people who are not bitten by mosquitos. So, there is a hope that bites, in the not so distant future, will be preventable:
Scientists have identified insect repelling chemicals produced by people who don't get bitten by mosquitoes and will be revealing how they made their discovery at the Royal Society Summer Science Exhibition which opens today (3 July 2006).
The teams at Rothamsted Research and Aberdeen University, who previously answered the long running question of why some people get bitten and others don't, have now isolated chemicals present in the body odour of people who naturally repel insects and have filed patents.
"Those of us who don't get bitten by mosquitoes produce unattractive chemicals, which mask their otherwise attractive odours", said research leader, Professor John Pickett. "Humans produce hundreds of different chemicals so it has been challenging to identify the particular chemicals that mosquitoes respond to".
The scientists used a technique known as gas chromatography-electroantennography' to identify which components of the odour the insect can detect.
"Gas chromatography allows us to separate out the eau de human' into its individual chemical components. The electroantennography then allows us to simultaneously record the responses in the mosquito's antennae." Said Dr James Logan, who is working with Professor Pickett at Rothamsted.
The team are hopeful that their detailed research findings, which have been submitted for publication in a leading scientific journal, may lead to the development of effective natural' insect repellents and may also result in new control methods for biting pests responsible for livestock losses and the spread of human illnesses, such as malaria, dengue fever and yellow fever in developing countries. Until the results have been published, the team cannot reveal the details of specific chemical compounds.
The researchers are now carrying out trials to test their effectiveness in preventing mosquito bites.
Professor Pickett added: "We are currently testing the natural compounds by comparing them with World Health Organisation approved insect repellents on individuals known to be attractive to mosquitoes we hope to publish the results of these trials soon."
Visitors to the Summer Science Exhibition can test their 'attractiveness' to mosquitoes, without the risk of getting bitten, using another piece of Rothamsted kit, an olfactometer'. Volunteers are invited to place their hand in one chamber and mosquitoes are exposed to a choice of two airstreams, one of which is laced with odour from the volunteer's hand. The mosquito's behaviour in response to the smell can then be observed to determine if a volunteer is attractive' or repellent' to mosquitoes.
Edited by pundabee, 23 July 2006 - 04:27 PM.
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