title: Repellency and efficacy of a 65% permethrin spot-on formulation for dogs against Aedes aegypti (Diptera: Culicidae) mosquitoes.
abstract: A topically applied 65% permethrin spot-on (Defend EXspot Treatment for Dogs, Schering-Plough Animal Health) used for flea and tick control on dogs was evaluated for repellency and efficacy against the yellow fever mosquito, Aedes aegypti, a vector of canine filariasis. Six dogs were randomly assigned to receive a single application of 65% permethrin on Day 0 (n=3) or to remain untreated as controls (n=3). Dogs were anesthetized and exposed to 100 unfed, female mosquitoes in screened cages for 2 hours on Days -6, -4, -1, 0, 1, 7, 14, 21, and 28. Mosquito landing rates, engorgement rates, and mortality were determined for each mosquito challenge. Cages were thoroughly cleaned after each mosquito challenge. Treatment of dogs with 65% permethrin reduced the mosquito landing rates by 96.3% 6 hours after treatment and by 82.5% on Day 1. Mosquito mortality, relative to the control group, was 28.2% 6 hours after treatment, ranged from 84.0% to 90.9% through Day 21, and declined to 50.3% 28 days after treatment. Successful feeding by mosquitoes was significantly (P=.05) reduced on Days 1 through 28. The 65% permethrin spot-on treatment killed and repelled significantly (P =.05) more mosquitoes on treated dogs versus untreated dogs for 28 days after treatment.
mesh_terms: D000279:Administration, Cutaneous; D000330:Aedes / Q000187:drug effects*; D000818:Animals; D002626:Chemistry, Pharmaceutical; D004199:Disease Vectors; D004283:Dog Diseases / Q000517:prevention & control*; D004285:Dogs; D005260:Female; D005368:Filariasis / Q000517:prevention & control / Q000662:veterinary*; D007302:Insect Repellents / Q000008:administration & dosage* / Q000494:pharmacology; D007306:Insecticides / Q000008:administration & dosage* / Q000494:pharmacology; D008297:Male; D009032:Mosquito Control / Q000379:methods; D026023:Permethrin / Q000008:administration & dosage* / Q000494:pharmacology
chemical_list: D007302:Insect Repellents; D007306:Insecticides; D026023:Permethrin