Cost-Effectiveness of Treatment for Canine Parasites in Remote Indigenous Communities

Zoonotic canine parasites and the vector-borne diseases they may carry can cause high morbidity and mortality in dogs and people. Many remote Indigenous communities in northern Australia have numerous free-roaming dogs, tropical climates favouring parasite development, and limited access to veterinary care, which can promote high prevalence of zoonotic parasites. To successfully combat parasites, treatment programs are needed, which are effective in reducing parasite burden and prevalence as well as being cost-effective and feasible. We compared canine parasite treatments in a Torres Strait Islander community setting, including oxibendazole/praziquantel tablets (OXI), moxidectin/imidacloprid spot-on (MOX), off-label oral ivermectin (IVM), afoxolaner chews (AFO), and flumethrin/imidacloprid collars (FLU). Cost surveys estimated the total annual and per-dog cost of each program. Markov modelling determined the cost per dog free of infection for each program using a government payer perspective over six-month and four-year time horizons. The annual cost per dog treated was $54.53 for OXI, $95.44 for MOX, $22.85 for IVM, $219.79 for AFO and $133.95 for FLU. IVM was less costly and more effective than other treatments against hookworm. FLU dominated in ectoparasite treatment. Sensitivity analyses supported these results. This study contributes cost-effectiveness data to inform parasite treatment program policy with aims of significant reductions in zoonotic canine parasite prevalence and subsequent reductions in environmental contamination with infectious parasite stages.