A wind tunnel bioassay system for screening mosquito repellents

A wind tunnel bioassay system to screen mosquito repellents is described. A wind tunnel is utilized to exploit the upwind flight response of host-seek ing mosquitoes. Mosquitoes within the wind tunnel are activated with human breath, fly upwind, and land on heated chick skins. This behavioral sequenc e results in a consistently high percentage of the test population approach ing repellent or control stimuli. The bioassay system is calibrated with di ethyl methylbenzamide against Aedes aegypti and demonstrates a reproducible dose-response relationship. The persistence of diethyl methyl benzamide af ter a 1-h period is also recorded. The design of the bioassay system permit s simultaneous, independent testing of 3 candidate repellents. The wind tun nel bioassay system is compared to other techniques for evaluating mosquito repellents.