New research delves into mosquito behaviour

Scientists in Hertfordshire have published new research which might help explain why some people suffer more mosquito bites than others.

A research student at Rothamsted Research, James Logan, discovered that certain people issued 'masking' odours, which made them 'unattractive' to mosquitoes.

Mr Logan's discovery builds on earlier studies conducted on cattle at the facility, in collaboration with the Danish Institute of Agricultural Science. A team, led by Professor John Pickett, found that the number of flies attracted to a herd, depended on certain cows being present. The scientists found that key 'unattractive' cows gave out different chemical signals to the others and when they were moved to a different field, the number of flies, which landed on the herd, increased.

Mr Logan and Professor Jenny Mordue, from the University of Aberdeen, performed tests on yellow fever mosquitoes, to test their reaction to odours from human volunteers. The tests involved placing the mosquitoes into a y-shaped tube and giving them the option of moving upwind down either branch – the air flowing down one branch was laced with the odour from a volunteer's hands.

The researchers said that the results showed that differential attractiveness seemed to be due to compounds that "switch off' attraction, by either acting as repellents or masking the attractant components of human odour. This conflicts with the theories of other research groups, who had suggested that 'unattractive' individuals did not possess the 'attractive' components that drew mosquitoes to certain people.

Further tests will now be carried out on the effect whole body odour has on mosquitoes, by using foil sleeping bags to collect odours from volunteers.

Mr Logan said: “By identifying these key components and understanding how they work we could be closer to new methods of protection from these biting pests that cause losses in livestock and irritation and illness in humans."

(KMcA/SP)