Susceptibility and Disease Progression in Calomys callosus: A Robust Rodent Model for Investigating Malaria-related Anemia

Malaria is a parasitic disease of high public health importance, with malarial anemia being one of its most severe and frequent complications, particularly in children from endemic areas. Murine experimental models, such as the BALB/c mouse, have been widely used to study malaria pathogenesis. However, gaps remain regarding the faithful reproduction of the mechanisms involved in associated anemia. In this context, the rodent Calomys callosus has emerged as a promising alternative for the study of parasitic diseases. This study evaluated the susceptibility of C. callosus to infection with Plasmodium berghei ANKA, with an emphasis on the characterization of clinical, parasitological, and hematological parameters. Animals were infected with different doses of parasitized red blood cells and monitored for morbidity, parasitemia, body weight, survival, and hematological changes. The results showed that animals infected with 1×10⁷ parasitized red blood cells exhibited higher parasitemia, more pronounced clinical signs, and more evident histological findings at this dose. Anemia was also observed, characterized by neutrophilia, thrombocytopenia, and anisocytosis, as well as reduced hematocrit and lower survival rates. These findings support the potential of C. callosus as an experimental model for studying malaria, particularly in the context of malarial anemia, and suggest its usefulness in research focused on pathophysiology and the development of new therapies.