Pathogenicity of Drug-resistant Canine Isolate of Trypanosoma brucei brucei in Rats

Background: Trypanosomosis is a neglected tropical disease. Drug resistance in trypanosomosis has been on the increase in recent years. It is presumed that drug resistant trypanosomes are less pathogenic and may be very suitable for rodent models of human African trypanosomosis (HAT). Methods: The T. b. brucei used was locally isolated from a dog and characterized by PCR. Drug resistance trait of the isolate was evaluated using diminazine aceturate and isometamidium chloride. Healthy rats were inoculated with the isolate, IP. Some haematobiochemical parameters were evaluated. Three rats were euthanized on day 70 P1 and necropsied. Data generated from the study were analyzed by student's t-test and significance was accepted at probability, p<0.05. Result: The isolate was confirmed to be drug resistant T. b. brucei and caused no mortalities in the infected rats. The low pathogenicity in rats was discussed and the typical CNS lesions of chronic-stage HAT produced by the isolate makes it a suitable candidate for rodent models of HAT.