What mosquitoes want in a snack

THE SUMMER has seen mosquitoes numbers rise in France, but have you ever wondered why the biting pests seem to find some people more tasty than others?

You’re not alone. A Smithsonian report revealed that mosquitoes seem to find an estimated 20% of people especially delicious.

Popular wisdom has blamed everything from age, to skin tone or “sweet blood”, but Jean-Baptiste Ferré, an entomologist at EID Méditerranée, says much of it is to do body odour and heat.

Mosquitoes have a powerful sense of smell, and are initially attracted by the carbon dioxide we breathe out, Mr Ferré said in an article on Le Nouvel Observateur.

Heat and body odour caused by sweat are also tempting to mosquitoes.

One study, he said, suggested that people who consumed more beer were more attractive to mosquitoes.

It is not the smell of alcohol that appeals, he said, but how the alcohol is assimilated into the human body. Alcohol consumption increases respiratory rates, which means people emit more CO2. It can also make you sweat, which releases body odour

After detecting our carbon dioxide emissions from some distance, mosquitoes tend to choose their “prey” by smell once they get closer.

Ill people are more attractive to mosquitoes, because their metabolism is higher and they emit more CO2, and also body heat as they fight infection - both of which attract the insects.

Pregnant women, too, have been found to attract roughly twice as many mosquito bites, because they breathe out more carbon dioxide and are on average about 1.26F warmer.

Young children and the elderly are more prone to being bitten, Mr Ferré said, because they are less likely to be able to successfully swat the insect. On the whole, however, children are less likely to be bitten because they are smaller and emit less CO2, making them more difficult for mosquitoes to find.