Reduction of mosquito biting pressure by timed-release 0.3% aerosolized geraniol

We conducted a study to determine the degree of personal protection provided by the Terminix^® ALLCLEAR^® Mosquito Mister - Lantern Edition. This outdoor unit was operated to disperse an aerosolized aqueous 0.3% geraniol emulsion in timed-release intervals of 5.0, 7.5, and 10.0min. Human volunteers participated in landing catch experiments to test the effect of geraniol sprayed at pre-set time intervals, at two distances: (1) 18ft (5.49m), the maximum effective distance claimed by the manufacturer, and (2) 9ft (2.74m), half the effective distance from the unit. When aerosolized geraniol was dispensed, reductions in biting pressure (landing, probing and biting mosquitoes) of Culex pipiens and Aedes albopictus, at all times and distances, were evident compared to dispensation of the water spray control. The degree of protection correlated well with the distance from the subject and the time interval of releases. The 5min time interval mode reduced overall biting pressure by more than 90% at 9ft (2.74m) and 18ft (5.49m). Reduction of biting pressure in the 7.5min mode was still well over 80% and even in the 10min mode, overall protection was slightly above 80% at a distance of 9ft. The lowest but still reasonable protection level was observed in the 10min mode, at the periphery of the area the unit claims to protect (300ft²), with a biting pressure reduction of approximately two-thirds.