The carbon dioxide we exhale and the odors that emanate from our skins are the vital factors that attract female mosquitoes to bite and spread diseases such as malaria, dengue and yellow fever.
Entomologists at the University of California, Riverside, studied how female Aedes aegypti-mosquitoes that transmit yellow fever and dengue-respond to plumes of carbon dioxide and human odor.
Ring Carde, a distinguished professor of entomology at the University of California, and Teun Dekker, an assistant professor at the Swedish University of Agricultural Research, found that puffs of exhaled carbon dioxide first attract these mosquitoes, which then proceed to follow a broad skin odor plume, eventually landing on a human host.
The results could clue scientists on how odors can be used in traps for intercepting and capturing host-seeking mosquitoes.
"Carbon dioxide induces a faster and more direct upwind orientation than skin odor," said Carde.
"Our experiments show that the response of yellow fever mosquitoes to skin odor requires an exposure longer than that of carbon dioxide to induce upwind flight," he added.
The study will appear in the October 15 issue of the Journal of Experimental Biology.