Concurrent Triple Parasitic Infection (Ctenocephalides canis, Rhipicephalus sanguineus, and Toxocara canis) in a Domestic Dog from Bangladesh: Clinical Management and Zoonotic Implications

Background Mixed parasitic infections are prevalent in dogs, often leading to significant clinical issues and posing zoonotic risks to humans. Dogs can simultaneously harbor ectoparasites such as fleas and ticks and endoparasites such as gastrointestinal nematodes. These parasites can induce dermatological and gastrointestinal disorders and serve as vectors or reservoirs for zoonotic infections. This case report describes a rare triple parasitic co-infection involving Ctenocephalides canis , Rhipicephalus sanguineus , and Toxocara canis in a domestic dog in Bangladesh and highlights the diagnostic approach and effective treatment strategy. Methods A 2-year-old male local breed dog presented to the veterinary clinic at Bangladesh Agricultural University, Mymensingh, Bangladesh, exhibiting severe pruritus, poor body condition, and diarrhea. Parasites were collected and identified through gross examination and detailed morphological analysis under a stereomicroscope. Key diagnostic features included cervical alae in T. canis , genal and pronotal combs in C. canis , and a hexagonal basis capitulum in R. sanguineus . Treatment consisted of an oral combination of sarolaner (1.2 mg/kg), moxidectin (24 µg/kg), and pyrantel pamoate (5 mg/kg), accompanied by supportive therapy and environmental control measures. Main results Morphological examination confirmed the presence of all three parasite species, thereby indicating a concurrent triple infection. Following treatment, clinical improvement was observed within 48 hours, characterized by a marked reduction in pruritus and improved appetite. A follow-up examination at 14 days revealed no visible ectoparasites and a negative fecal flotation test for T. canis eggs. Complete clinical recovery was recorded during the 30-day follow-up period. Conclusions This case underscores the clinical and zoonotic significance of mixed parasitic infections in dogs. Routine parasitic screening and preventive measures are crucial within a One Health framework to minimize zoonotic transmission risks.