The mechanism mosquitoes use to zero in on their targets has been discovered by scientists in New York.
It is already known that the insects are very sensitive to carbon dioxide in exhaled breath. Now a team led by Rockefeller University has found that they sense the gas using protein receptors in the structure extending from their jaws.
Lead researcher Professor Leslie Vosshall said: "Insects are especially sensitive to carbon dioxide, using it to track food sources and assess their surrounding environment.
"The neurons in insects that respond to carbon dioxide were already known, but the molecular mechanism by which these neurons sense this gas was a mystery.
"Though we don't know what other proteins might be involved in the signalling pathway, the identification of the carbon dioxide receptor provides a potential target for the design of inhibitors that would act as an insect repellent.
It is either that or we stop breathing!