Season-long control of flea and tick infestations in a population of cats in the Aeolian archipelago using a collar containing 10% imidacloprid and 4.5% flumethrin

Cats that have outdoor access are highly exposed to ticks, fleas, mites and flying insects, though the risk to become infested by arthropods is less perceived in cats than in dogs. This has resulted in fewer treatment and prevention options being available for cats than for dogs. A collar containing a combination of 10% imidacloprid and 4.5% flumethrin (Seresto®, Bayer Animal Health) is available for cats and licensed with claims against ticks and fleas for 7–8 months. Following the assessment of the efficacy of the collar against Leishmania infantum infection in privately owned cats living in the Aeolian archipelago, herein we report the efficacy of the collar in the treatment and prevention of tick and flea infestations in the same population of cats over a period of one year of observation. At the inclusion day (Study Day 0, SD 0), cats were visited and examined for ectoparasites (i.e., flea combing and tick thumb counts) and allocated to group 1 (G1; n = 104; cats treated with Seresto® collar) or group 2 (G2; n = 100; untreated controls) and further checked at SDs 210, 270 and 360 (study closure). At SD 0, G1 and G2 had a comparable percentage of cats infested by fleas (45.2% and 49.0%; χ2 = 0.164; P = 0.6859) and ticks (6.7% and 14.0%; χ2 = 2.946; P = 0.0861). The number of cats infested by fleas was reduced in G1, being 8.3%, 0% and 3.8% on SDs 210, 270 and 360, respectively, resulting in efficacies against fleas of 79.4%, 100% and 93.6% on SDs 210, 270 and 360. None of the cats in G1 was found infested by ticks after the application of the collar, whereas in G2 ticks were observed on 15.7%, 4.8%, 17.5% of the cats at the different follow up visits, leading to an overall efficacy against ticks of 100%. A total of 375 ectoparasites were collected from cats, being 249 fleas (six Ctenocephalides canis, 240 Ctenocephalides felis and three Nosopsyllus fasciatus) and 126 ticks (87 Ixodes ventalloi and 39 Rhipicephalus pusillus). Field data gathered herein confirm a high efficacy of the collar in the prevention of tick and flea infestations on cats. This is of great importance both for the primary role of fleas and ticks as blood feeding parasites and, more importantly, because of their role as vectors of pathogens causing diseases of veterinary and medical importance.