Human trypanosomiasis in Ethiopia

African human trypanosomiasis was first seen in Ethiopia in March 1967. Between March 1967 and March 1968, 4 cases were recorded; in the following 12 months the total had risen to 95. The disease occurs mainly in an area of southwestern Ethiopia bounded to the north by the Baro River, to the south by the Akobo River and to the east by the escarpment leading up to the central Ethiopian plateau: its western limits are uncertain. Within this area there are centres of infection, associated mainly with the Gilo River and a low-lying moist region north of it. The disease is of the acute type, caused by Trypanosoma brucei rhodesiense. The present paper introduces the subject and describes the situation in the northern part of the affected area along the Baro River. Two men probably acquired the infection in that region in 1967 and one in 1968. A blood film survey of 430 people in 1968 failed to reveal any further infections, and it is probable that here the disease is a zoonosis, transmitted to man sporadically by Glossina morsitans and, perhaps, G. pallidipes and G. fuscipes.