CHAPTER VI 

 TRYPANOSOMES AND SLEEPING SICKNESS 



Importance of Trypanosome Diseases. — One of the blackest 

 clouds overhanging the civilization of tropical Africa is the 

 terrible scourge of sleeping sickness, a disease caused by protozoan 

 parasites known as trypanosomes. The destiny of the equatorial 

 parts of Africa depends largely on the issue of the struggle of 

 medical science against this haunting malady. The ravages of 

 the disease were well known to the old slave traders, and the 

 presence of " lazy niggers " lying prostrate on wharves and 

 decks with saliva drooling from their mouths, insensible to emo- 

 tions or pain, was a familiar sight. It did not take these astute 

 merchants long to find that death was the inevitable outcome of 

 the disease, and they very soon recognized swollen glands in the 

 neck as an early symptom and refused to accept as slaves negroes 

 with swollen glands (see Fig. 24). Nevertheless sleeping sick- 

 ness must often have been introduced with its parasites into 

 various parts of North and South America, as it frequently is even 

 at the present time, and only the absence of a suitable means of 

 transmission has saved the Western Hemisphere from being 

 swept by it. 



Up to about thirty years ago sleeping sickness was confined to 

 a limited part of tropical West Africa, but with the opening up of 

 Central Africa by whites and the consequent movements of 

 disease-carrying inhabitants to new portions of the continent, 

 the afflicted country was greatly extended. The great explorer 

 Stanley, in his expedition to reach Emin Pasha, was almost un- 

 questionably responsible for the introduction of the scourge into 

 Uganda and the lake regions of Central Africa in 1888, where it 

 had hitherto been unknown. In one district of Central Africa 

 the population was reduced from 300,000 to 100,000 in the course 

 of seven years, from 1901 to 1908, and there are records of whole 

 villages and islands being depopulated. 



In 1909 there occurred a case of sleeping sickness contracted in 



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