Activation, orientation and landing of female Culex quinquefasciatus in response to carbon dioxide and odour from human feet: 3-D flight analysis in a wind tunnel

• Published in: Medical and veterinary entomology Vol. 25; no. 1; pp. 94 - 103
• Main Authors: LACEY, E.S, CARDÉ, R.T
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01-03-2011; Wiley Subscription Services, Inc
• Subjects: anemotaxis; Animals; Carbon dioxide; Carbon Dioxide - pharmacology; Culex - physiology; Culex quinquefasciatus; Culicidae; Diptera; Female; Females; Flight, Animal; Foot; host seeking; human body odour; human foot odour; Humans; Mosquitoes; Odorants; Odors; Orientation; wind tunnel; Wind tunnels
• ISSN: 0269-283X; 1365-2915
• DOI: 10.1111/j.1365-2915.2010.00921.x

This study investigated the interaction between carbon dioxide (CO₂) and human foot odour on activation, upwind orientation and landing of host-seeking female Culex quinquefasciatus (Say) (Diptera: Culicidae) in a wind tunnel. More mosquitoes landed on warmed glass beads coated with foot odour than on clean beads; adding a plume of 4% CO₂ did not influence the proportion of mosquitoes landing. A second experiment used 3-dimensional video tracking to assess flight performance. Activation was more rapid with CO₂ and with CO₂ + foot odour than with clean air or with foot odour alone. Upwind flights were fastest with CO₂ and with clean air, and slowest with foot odour; the CO₂ + foot odour treatment overlapped the previous three treatments in significance. Flight headings tended more towards due upwind with CO₂ and with clean air than with CO₂ + foot odour or with foot odour alone. In both experiments, many mosquitoes flew upwind in clean air. There was little evidence of females changing course upon entering or exiting the CO₂ plume or reacting to foot odour during flight.