India's tourist industry would flourish if they could finish
off the midges and mosquitoes . Giving every one a quota of ten a day
to kill could work .

excerpt sunday times

The scientists first collected chemicals secreted from the skin of
volunteers who lay naked in a sealed foil bag. The body odour was
drawn upwards by passing air through the bag.

Live mosquitoes and midges were then placed in a Y-shaped tube and
given the choice of moving up or down either branch. The air flowing
down one was laced with the odour from the volunteer while that on the
other was left pure. When the insects moved down the tube without the
odour they were judged to be repelled by the smell; moving down the
side with the odour meant they were attracted to it.

Analysis of the ?unattractive? odours suggested some people emitted a
range of 11 compounds that repelled the insects or prevented them
detecting attractive smells. The scientists believe that these
compounds did this partly by acting as repellents and partly by
masking the attractive components of human odour that mosquitoes use
to home in on a meal.

The research team will not disclose what compounds have been
identified because they hope to put their knowledge to commercial use.
The midge problem in Scotland not only puts off tourists, but has been
a major nuisance in making films and television programmes such as
Monarch of the Glen.

Stars of the BBC show, which is filmed at Ardverikie, on the shores of
Loch Laggan, have tried a number of techniques to avoid being bitten,
including pulling fine-meshed hairnets over their faces during breaks
in filming.

The research, funded by the Scottish executive and the Biological
Sciences Research Council, differs from previous theories suggesting
that unattractive individuals simply lack the components mosquitoes
like. Instead, it finds they actively repel the insects.

Scientists hope a repellent using some of these compounds can be
sprayed onto material which would allow it to be sewn into clothes or
a hat. They believe it will be more effective than other repellents
because it recreates highly effective natural chemicals.

The news will be welcomed in Scotland, home to more than 30 species of
biting midge. It is estimated that in midge-infested areas, such as
western Scotland, one hectare can be home to about 24m larvae. Most
feed off farm livestock, deer or birds, but about five species are
attracted to humans.

The most aggressive is the Highland biting midge ? Culicoides
impunctatus ? which is responsible for 90% of attacks.