Here in Mauritius, mosquitoes are in paradise. The male mosquitoes
have all the fruits they'll ever dream of – god knows whether they
actually dream – all year long while the female mosquitoes can choose
from a numerous number of tourists to feed on.

It is of no surprise that tourists get bitten more than we, locals
do. And the reaction which occurs on the tourists' skin is quiet
unusual to me. A large red swelling develops. It is about twice the
size that the one which would have formed on my skin if I was to get
bitten. Apparently the bite that a tourist receives is also more
irritant. In my opinion, this is because foreigners are not as used
to getting mosquito bites as Mauritians. But one thing is for sure
though: some people do get bitten more than others.

Why is this so? Or rather, why are some people bitten less? James
Logan, a research student at the Biotechnology and Biological Sciences
Research Council (BBSRC) has found that some people give off 'masking'
odours that prevent mosquitoes from detecting them. Another study,
done earlier by Professor John Pickett and his team, showed that the
number of flies circulating around a herd depended on certain cows
being present. Professor Pickett and his team discovered that
unattractive – to mosquitoes at least - individuals gave out different
chemical signals from other cows. To be sure about this fact, the
unattractive cows were removed and the number of flies bothering the
herd did indeed increase. These 'ordinary' cows had not been
camouflaged by the unattractive cows' special 'masking' odour and
therefore the flies were attracted to the 'ordinary' cows.

After some other experiments, it was concluded that the famous
'masking' odours were acting as repellents or as a cover up. This
finding could lead to a new type of insect repellent. These would be
both safer and more effective.

Next time you get bitten, just think that the mosquitoes are not
attracted by your 'sweet' blood but by your own odour.

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