Drug-Resistance Shown by Trypanosomes Following 'Antrycide' Treatment

Abstract

THE control of bovine trypanosomiasis by chemotherapy has recently received a welcome stimulus owing to the discovery of the trypanocidal properties of the new drug 'Antrycide'. The original investigators (Curd and Davy, 1949 ¹) have shown its curative and prophylactic action in experimental animals against several species of trypanosomes infecting man and cattle, and at Entebbe, Uganda, we have shown² that the soluble sulphate salt of 'Antrycide', in doses of 3–5 mgm. per kilo, cured Trypanosoma simœ infections in pigs. One pig, however, infected with T. simœ and dosed with the relatively insoluble chloride salt at 2 mgm. per kilo, relapsed. A second immediate treatment with 5 mgm. per kilo 'Antrycide' sulphate failed to cure this pig, and the relapse strain was considered, therefore, to have developed drug-resistance in this short time.