Efficacy Of A Novel Area-Repellent Aerosol Formulation Against Mosquitoes And Flies (Diptera: Culicidae, Muscidae)

Abstract:
Field studies of two area repellent aerosol formulations with transfluthrin and permethrin active ingredients were carried out against mixed freshwater mosquitoes near Humpty Doo, Northern Territory and against flies (a mixed population of house flies, Musca domestica and bush flies Musca vetustissima) in Bell, South West Queensland, Australia. The mosquito test site was adjacent to a breeding area, with a large population of biting mosquitoes. Fly repellency testing was conducted in the milking shed of a dairy farm with a large resident fly population. Non-absorbent (glazed tile) and absorbent (plywood) substrates were sprayed with the formulations and exposed to the ambient conditions. For the mosquito study, substrates were located adjacent to seated human test subjects. The test subjects counted all mosquito landings on the visible areas of their body during a 5 minute period every 2 hours for 6 hours. Fly evaluation was conducted in a similar manner, except that human assessors counted all fly landings on surfaces within a 1 metre radius of where they were seated. There were no significant differences in efficacy between the high and low active level formulations for both mosquitoes and flies. The lower active level formulation (0.5% transfluthrin and 0.05% permethrin) gave a reduction of 96.3% over 6 hours for glazed tiles, compared to the untreated controls, and a reduction of 80.0% for plywood. For flies, the respective reductions for the same rate were 81.4% and 79.0%. These studies demonstrated that both formulations provided effective area protection from mosquitoes and flies for up to 6 hours after application, on both absorbent and non-absorbent surfaces.