Onchocerciasis in expatriates on the Ivory Coast

Six cases of onchocerciasis were diagnosed in expatriates working on a hydroelectric dam project in Taabo (Ivory Coast) between 1977 and 1978. Taabo is in the forest area of the Bandama River, where onchocerciasis is hyperendemic. The six patients had lived in the area from 20 months to four years. In the early 1970s four of them had worked at the Kossou Dam, a similar project 125 miles up the Bandama River. Diagnoses were confirmed by demonstrating microfilariae in biopsy specimens taken from the skin overlying the iliac crest. A seventh case was diagnosed clinically as tropical filarial pulmonary eosinophilia. The six patients with microfilariae in the skin were treated successfully with diethylcarbamazine (Notezine, Hetrazan) and suramin (Moranyl). The patient with pulmonary involvement responded dramatically to treatment with diethylcarbamazine. The overall effects of onchocerciasis are poorly understood, though it is now one of the major tropical diseases, affecting millions of people living in central and western Africa, Yemen, and Central America. Medical treatment is successful, but few preventive measures are available for the disease; larvicides are subject to resistance, and their effects are transient.