title: Evaluation of barrier treatments on native vegetation in a southern California desert habitat.
abstract: Treating perimeters with residual insecticides for protection from mosquito vectors has shown promise. These barrier treatments are typically evaluated in temperate or tropical areas using abundant vegetation as a substrate. However, there is an emerging interest to develop this technology to protect deployed US troops in extreme desert environments with sparse vegetation. We used a remote desert area in the Coachella Valley, California, to 1) evaluate bifenthrin barrier treatments on native xeric vegetation and 2) compare treatments applied with electrostatic and conventional spray technologies. Through a combination of laboratory bioassays on treated and control vegetation sampled at specific intervals over 63 days, synchronized with field surveillance of mosquitoes, we measured the temporal pattern of bioactivity of bifenthrin barriers under natural hot, dry, and dusty desert conditions. Regardless of spray technology, mosquito catch in treated plots was about 80% lower than the catch in control plots 1 day after treatment. This reduction in mosquito numbers in treated plots declined each week after treatment but remained at about 40% lower than control plots after 28 days. Field data were corroborated by results from bioassays that showed significantly higher mosquito mortality on treated vegetation over controls out to 28 days postspray. We concluded that barrier treatments in desert environments, when implemented as part of a suite of integrated control measures, may offer a significant level of protection from mosquitoes for deployed troops. Given the comparable performance of the tested spray technologies, we discuss considerations for choosing a barrier treatment sprayer for military scenarios.
authors: United States Department of Agriculture, Agricultural Research Service, Center for Medical, Agricultural, and Veterinary Entomology, 1600 SW 23rd Drive, Gainesville, FL 32608, USA.
authors: Seth C
authors: SC
authors: Britch
authors: Kenneth J
authors: KJ
authors: Linthicum
authors: Wayne W
authors: WW
authors: Wynn
authors: Todd W
authors: TW
authors: Walker
authors: Muhammad
authors: M
authors: Farooq
authors: Vincent L
authors: VL
authors: Smith
authors: Cathy A
authors: CA
authors: Robinson
authors: Branka B
authors: BB
authors: Lothrop
authors: Melissa
authors: M
authors: Snelling
authors: Arturo
authors: A
authors: Gutierrez
authors: Hugh D
authors: HD
authors: Lothrop
mesh_terms: D000818:Animals; D002140:California; D009033:Culicidae; D005260:Female; D007306:Insecticides; D009032:Mosquito Control / Q000295:instrumentation / Q000379:methods*; D010573:Pesticide Residues; D011722:Pyrethrins; D013997:Time Factors
chemical_list: D007306:Insecticides; D010573:Pesticide Residues; D011722:Pyrethrins; C099952:bifenthrin