Assessing the efficacy of three trypanocidal drugs in controlling Trypanosoma evansi.

Trypanosoma evansi is an emerging zoonotic threat causing significant economic and health issues, especially in tropical and subtropical regions. Due to limited effective trypanocidal agents and increasing drug resistance, this investigation sought to evaluate the therapeutic efficacy of quinapyramine sulfate and chloride, melarsamine hydrochloride, and diminazene aceturate in 72 female Swiss albino mice. Each drug was administered at two dosages: quinapyramine (3 and 6 mg/kg), melarsamine hydrochloride (0.25 and 0.5 mg/kg), and diminazene aceturate (3.5 and 7 mg/kg). The efficacy was evaluated based on parasitaemia, relapse patterns, body weight changes, hematological and biochemical profiles, postmortem and histopathological findings. The results showed quinapyramine was ineffective at both dosages. However, doubling the therapeutic doses of melarsamine hydrochloride and diminazene aceturate enhanced their efficacy, although parasitaemia relapsed in all cases. Blood biochemical analyses revealed infection-induced anemia, leukocytosis, eosinophilia, and significant reductions in total protein, serum albumin, and globulin levels. Histopathological examination revealed evidence of degenerative pathology and tissue injury within the hepatic, splenic, cardiac, and renal parenchyma in all experimental groups with varying degrees. These findings suggest that melarsamine hydrochloride, at higher doses, may offer a more effective treatment for T. evansi infection, although relapse remains a challenge.