title: Evaluation of efficacy and human health risk of aerial ultra-low volume applications of pyrethrins and piperonyl butoxide for adult mosquito management in response to West Nile virus activity in Sacramento County, California.
abstract: The Sacramento and Yolo Mosquito and Vector Control District (SYMVCD, also referred to as "the District") conducts surveillance and management of mosquitoes in Sacramento and Yolo counties in California. Following an increase in numbers and West Nile virus (WNV) infection rates of Culex tarsalis and Culex pipiens, the District decided on July 26, 2007, to conduct aerial applications of Evergreen EC 60-6 (60% pyrethrins: 6% piperonyl butoxide) over approximately 215 km2 in the north area of Sacramento County on the nights of July 30, July 31, and August 1, 2007. At the same time, the District received notification of the first human WNV case in the area. To evaluate the efficacy of the applications in decreasing mosquito abundance and infection rates, we conducted pre- and post-trapping inside and outside the spray zone and assessed human health risks from exposure to the insecticide applications. Results showed a significant decrease in abundance of both Cx. tarsalis and Cx. pipiens, and in the minimum infection rate of Cx. tarsalis. Human-health risks from exposure to the insecticide were below thresholds set by the US Environmental Protection Agency.
authors.affiliation: Sacramento-Yolo Mosquito and Vector Control District, 8631 Bond Road, Elk Grove, CA 95757, USA.
authors.forename: Paula A
authors.initials: PA
authors.lastname: Macedo
authors.forename: Jerome J
authors.initials: JJ
authors.lastname: Schleier
authors.forename: Marcia
authors.initials: M
authors.lastname: Reed
authors.forename: Kara
authors.initials: K
authors.lastname: Kelley
authors.forename: Gary W
authors.initials: GW
authors.lastname: Goodman
authors.forename: David A
authors.initials: DA
authors.lastname: Brown
authors.forename: Robert K D
authors.initials: RK
authors.lastname: Peterson
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000818:Animals; D002140:California; D002648:Child; D002675:Child, Preschool; D009033:Culicidae; D005260:Female; D006801:Humans; D007223:Infant; D007303:Insect Vectors; D007306:Insecticides / Q000008:administration & dosage* / Q000633:toxicity; D008297:Male; D008875:Middle Aged; D009032:Mosquito Control; D010574:Pesticide Synergists / Q000008:administration & dosage* / Q000633:toxicity; D010882:Piperonyl Butoxide / Q000008:administration & dosage* / Q000633:toxicity; D011722:Pyrethrins / Q000008:administration & dosage* / Q000633:toxicity; D018570:Risk Assessment; D014901:West Nile Fever / Q000635:transmission; D055815:Young Adult
chemical_list: D007306:Insecticides; D010574:Pesticide Synergists; D011722:Pyrethrins; D010882:Piperonyl Butoxide