Comparative Speed of Kill, Repellent (anti-feeding) and Acaricidal Efficacy of an Imidacloprid/Flumethrin Collar (Seresto®) and a Fipronil/(S)-Methoprene/Eprinomectin/Praziquantel Spot-on (Broadline®) against Ixodes ricinus (Linné, 1758) on Cats

Abstract

Speed of kill, repellent (anti-feeding) and acaricidal efficacy of an imidacloprid 10 % (w/w) /flumethrin 4.5 % (w/w) collar (Seresto ® , Bayer) and a spot-on formulation of fipronil 8.3 % (w/v) /(S)-methoprene 10 % (w/v) /eprinomectin 0.4 % (w/v) /praziquantel 8.3 % (w/v) (Broadline ® , Merial) against artificiallyinduced infestations with Ixodes ricinus on cats, were assessed in a parallel group design, randomised, controlled study. Twenty-four cats were included and randomly allocated to treatment groups or a non-treated control group. Starting on Day (D) 7 after treatment until D28, cats were each infested with 50 I. ricinus at weekly intervals. Ticks were counted in situ on the cats at 6, 12 and 24 h and upon removal 48 h after each infestation.Based on arithmetic means, Seresto ® proved to be 100 % effective against adult I. ricinus at all assessment times (6, 12, 24 and 48 h after infestation) throughout the month-long study. Broadline ® was 0 % to 16.7 % effective at 6 h, 26.8 % to 50.0 % effective at 12 h, while at 24 h after infestation efficacy peaked at 81.5 % on D15 declining to 31.5 % on D29. Based on the 48 h tick counts, the efficacy of Broadline ® peaked at 100 % on D16 after treatment and decreased to 83.2 % by D30. The Seresto ® collar provided significantly faster speed of kill and better persistent acaricidal effectiveness against Ixodes ricinus on cats compared to Broadline ® spot-on. The additional repellent (anti-feeding) effect of Seresto ® prevents parasites from taking a blood meal and thereby reduces the risk of vector-borne disease pathogen transmission. S109ECtopar aSItES

Repellency effect of flumethrin pour-on formulation against vectors of Crimean–Congo haemorrhagic fever

“…The toxicity of flumethrin was 8 times higher than that of coumaphos against ticks. Some studies have shown that 1% flumethrin pour-on has 95-100% lethality for ectoparasites (17). Flumethrin can prevent disease transmission by ticks, fleas, mites and other ectoparasites due to its repellent property (preventing blood feeding) (17).…”

Vapor toxicity of five volatile pyrethroids against Aedes aegypti, Aedes albopictus, Culex quinquefasciatus, and Anopheles quadrimaculatus (Diptera: Culicidae)

“…For example, a recent study has shown vapors of metofluthrin and d ‐allethrin, which is a non‐fluorinated pyrethroid, both repelled and killed ticks . Conversely, flumethrin is a pyrethroid that is used primarily to repel or kill ticks on domestic animals . This pyrethroid has not been tested against mosquitoes, but flumethrin has been demonstrated to repel and kill Sand flies in the genus Phlebotomus Loew…”

“…The mortality recorded in prior studies is consistent, but measurements were performed in environments with limited control of exposure or in a way that did not exclude mosquitoes from physical contact with the compound . Mortality focused studies also have not attempted to characterize the range of outcomes on a dose response curve .…”

“…12 Conversely, flumethrin is a pyrethroid that is used primarily to repel or kill ticks on domestic animals. 13 This pyrethroid has not been tested against mosquitoes, but flumethrin has been demonstrated to repel and kill Sand flies in the genus Phlebotomus Loew. 14 The mortality recorded in prior studies is consistent, but measurements were performed in environments with limited control of exposure 2, 3,6 or in a way that did not exclude mosquitoes from physical contact with the compound.…”

“…14 The mortality recorded in prior studies is consistent, but measurements were performed in environments with limited control of exposure 2, 3,6 or in a way that did not exclude mosquitoes from physical contact with the compound. 13,14 Mortality focused studies also have not attempted to characterize the range of outcomes on a dose response curve. [4][5][6][7]12 As a result, it is difficult to determine if spatial repellent compounds may be tenable as mosquito adulticides despite numerous reports of the active ingredients killing mosquitoes.…”