Experiments performed by entomologists to study how female Aedes aegypti — mosquitoes that transmit yellow fever and dengue — respond to plumes of carbon dioxide and human odor demonstrate 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. Results from the study could clue scientists on how odors can be used in traps for intercepting host-seeking mosquitoes.