Efficacy of Effipro^® Duo against ticks (Rhipicephalus turanicus) in cats

Introduction

Tick infestations pose serious health problems to cats. As such the use of an effective topical acaricide on cats is important to protect these animals against the detrimental effects of ectoparasitic transmitted diseases and infestations. The objective of this randomised, blinded, controlled study was to evaluate the effectiveness of a fipronil-pyriproxyfen spot-on formulation (Effipro^® Duo, Virbac, Carros, France) against ticks (Rhipicephalus turanicus) on cats.

Materials and Method

Animals: Sixteen healthy adult cats (>6 months, 1.94 kg to 3.94 kg) were recruited. All cats were dewormed prior to initiation of the study and did not have resident tick or flea infestations at the initiation of the study. They had not been treated with a long acting topical or systemic acaricide/insecticide during the 12 weeks preceding Day 0. Cats were randomized into 2 groups with 8 cats each receiving either no treatment (Group 1) or Effipro^® Duo (Group 2).

Treatment: Effipro^® Duo (fipronil 50mg and pyriproxyfen 60mg - 0.5 mL pipette per cat) was applied once on Day 0. The cats were then observed hourly for four hours for possible adverse events and daily afterwards.

Exposure and measurements: Fifty R. turanicus (South African origin) were used in the artificial infestations of sedated cats. Adult ticks were unfed, at least one week old and had a balanced sex
ratio. Infestations were performed on days -7, -4, -2, 7, 14, 21 and 28 and tick counts (live or killed, free or attached engorged or not) were conducted 48h post-infections or post-treatment
(days -5, -2, 2, 9, 16, 23 and 30).

Analysis: The efficacy against ticks was calculated according to the formula: Efficacy (%) = 100 x (Mc – Mt)/Mc, using arithmetic or geometric mean number of live ticks on cats in the negative control group (Mc, group 1) and in the treated group (Mt, group 2) at a specific time point for immediate (Day 2) and persistent (Days 9, 16, 23 and 30) efficacy.

The groups were compared at each time point by an ANOVA or a Mann-Whitney Test. 

Results 

Conclusion 

Effipro^® Duo (fipronil-pyriproxyfen) has an immediate curative effect against existing tick infestations and prevents further tick infestations up to one month after administration to cats