Efficacy of single topical treatment of Selamectin (Revolution®) against Ancylostoma ceylanicum in experimentally infected cats.

Ancylostoma ceylanicum, a species of hookworm, is a common parasite of dogs and cats in the Asia-Pacific region. The objective of this study was to determine the efficacy of a single topical treatment of selamectin (Revolution®) against A. ceylanicum in experimentally infected cats. 12 kittens were injected with 300 infective stage larvae (L3) of A. ceylanicum by the subcutaneous route. Faecal samples were examined daily (days 7–15) for the presence of hookworm eggs. On day 18 kittens were stratified by faecal egg count and randomly allocated in equal numbers to control (n = 6) and treatment (n = 6) groups. Faecal egg counts were then performed daily (days 14–27) or every 3 days (days 28–51) until the end of the study and compared between the treated and control groups. Kittens in the treatment group were administered a single topical dose of selamectin (Revolution®), per label recommendations (6 mg/kg), on day 19. Kittens in the control group were not treated. At 4 days post-treatment, no hookworm eggs were detected in the treated group. Faecal samples from this group remained negative throughout the study, the treatment efficacy was 100% egg reduction (P < .0001). Average faecal egg counts remained high (558 ± 231 eggs per gram) in the untreated control group until the end of the study period. In conclusion, a single topical treatment of selamectin (Revolution®) at the recommended dose was highly efficacious against infection with A. ceylanicum in cats.