| Flight-limit and dilution-mediated models for wind effects on mosquito host-seeking behavior are explored in this thesis. Field experiments on human subjects and CDC light traps tested these models and also assessed the efficacy of DEET vapor for increasing the protective effects of wind velocity. Fan-driven application of wind and DEET vapor at 2 m/s significantly reduced mosquito orientation to, landing on, and probing of a human subject. CDC light-trap catches of mosquitoes were also reduced by addition of wind. This reduction fit a negative logarithmic function over the applied velocity range (0 to 3.7 m/s) and closely matched the theoretical dilution function as wind increases over a constant-release source. Increasing the CO2 release rate from 650 to 1,950 ml/min increased mosquito response for all wind velocities, but had no effect on the slope of the logarithmic response. There was no correlation between applied wind velocity and mosquito mass. Collectively, these data strongly support a dilution and not flight limit as the mode of action by which wind reduces mosquito host seeking. Outdoor fans as well as vertical or horizontal wind curtains are proposed as local protection tactics against nuisance mosquitoes in a backyard setting. |
