Evaluation of afoxolaner chewables to control flea populations in naturally infested dogs in private residences in Tampa FL,USA

Background: a study was conducted to evaluate the effectiveness of afoxolaner chewables to control flea populations in naturally infested dogs in private residences in tampa fl,usa. evaluations of on-animal and premises flea burdens,flea sex structure and fed-unfed premises flea populations were conducted to more accurately assess flea population dynamics in households. methods: thirty seven naturally flea infested dogs in 23 homes in tampa,fl were enrolled in the study and treated with afoxolaner chewables. chewables (nexgard® chewables; merial) were administered according to label directions by study investigators on study day 0 and once again between study days 28 and 30. flea infestations on pets were assessed using visual area thumb counts and premises flea infestations were assessed using intermittent-light flea traps on days 0,7,14,21,and once between study days 28-30,40-45,and 54-60. results: within 7 days of administration of afoxolaner chewable tablets,flea counts on dogs were reduced by 99.3 %. by one month post-treatment,total flea counts on dogs were reduced by 99.9 %,with 97.3 % (36/37) of the dogs being flea free. following the second dosing on study day 28-30,total on-dog flea burden was reduced by 100 % on days 40-45 and 54-60. on day 0,the traps collected a geometric mean of 18.2 fleas. subsequent reductions in emerging flea populations were 97.7 and 100 % by days 28-30 and 54-60,respectively. there were 515 total fleas (ctenocephalides felis felis) collected in the intermittent light flea traps on day 0,and 40.4 % of those fleas displayed visual evidence of having fed. seven days after initial treatment,only 13.1 % of the fleas contained blood and by day 14 only 4.9 % of the fleas collected in traps displayed evidence of having fed. on day 0,prior to treatment,60 % of the unfed fleas collected in intermittent-light flea traps were females,but by days 28-30,unfed males accounted for 78 % of the population. conclusions: this in-home investigation conducted during the summer of 2014 in subtropical tampa,fl demonstrated that afoxolaner chewables rapidly and effectively eliminated flea populations in infested dogs and homes. © 2015 dryden et al.; licensee biomed central.