Experimental Babesia microti infections in non-splenectomized Macaca mulatta

Area of Science:

• Veterinary Medicine
• Infectious Diseases
• Parasitology

Background:

• Babesia microti is an intraerythrocytic parasite causing babesiosis in humans and animals.
• Non-splenectomized hosts may experience more severe or prolonged infections.
• Understanding parasite dynamics in animal models is crucial for disease research.

Purpose of the Study:

• To evaluate the susceptibility of non-splenectomized rhesus macaques (Macaca mulatta) to Babesia microti.
• To characterize the course and duration of patent infections in this primate model.

Main Methods:

• Eight non-splenectomized rhesus macaques were intravenously inoculated with Babesia microti strains.
• Parasitemia levels were monitored to determine prepatent periods, peak parasitemias, and infection duration.

Main Results:

• Patent infections developed in 7 out of 8 inoculated macaques.
• Prepatent periods ranged from 15 to 46 days.
• Peak parasitemias varied from 496 to 3,906 organisms/mm³.
• Parasitemia persisted for at least 90 days in all infected animals, with one case lasting 559 days.

Conclusions:

• Non-splenectomized rhesus macaques are susceptible to Babesia microti infection.
• This primate model exhibits prolonged parasitemia, suitable for studying chronic babesiosis.
• Further research can utilize this model to investigate Babesia microti pathogenesis and treatment strategies.