Efficacy in cats of a novel topical combination of fipronil, (S)-methoprene, eprinomectin, praziquantel, against induced infestations of Echinococcus multilocularis

Although foxes are the main reservoir of Echinococcus multilocularis, it is recognized that dogs and cats also may become infected. In cats the infection and egg production rates are usually low. Nevertheless, cats are a potential source of transmission of E. multilocularis. Due to the high human medical significance of E. multilocularis infection, it is important in endemic areas that owned cats are dewormed regularly. This paper presents the efficacy results of a new topical formulation, Broadline® (Merial) tested against E. multilocularis infection in cats. Two blinded laboratory studies were conducted to evaluate this novel topical combination of fipronil, (S)-methoprene, eprinomectin, and praziquantel against E. multilocularis. In each study, purpose-bred cats were assigned randomly to two treatment groups of 10 cats each: one untreated control group and one group treated at the minimum therapeutic dose of 0.12 mL/kg bodyweight to deliver 10 mg fipronil, 12 mg (S)-methoprene, 0.5 mg eprinomectin and 10 mg praziquantel/kg bodyweight. The cats were inoculated orally with E. multilocularis protoscolices, 22 or 23 days before treatment. Based on necropsy and intestinal worm count, 8 or 11 days after treatment, the two studies confirmed 100% efficacy of Broadline® against adult E. multilocularis.