TRYPANOSOMA GAMBIENSE 199 



(1869) it had already been known as a blood parasite 

 in many of the lower animals. In 1901 Dr. Button, 

 of the Liverpool School, whilst investigating tropical 

 diseases in the Gambia Colony, discovered, in conjunction 

 with Dr. Forde, the parasite in the blood of a patient 

 under the care of Dr. Forde ; Dr. Dutton named it the 

 Trypanosoma gambicnse ; and then, in the year 1902, the 

 world was made aware by Bruce and Castellani of 

 the fact that the mysterious and deadly disease which 

 was rapidly spreading over Central Africa — Sleeping 

 Sickness — was due to the same parasite. Since then the 

 disease has been subjected to numerous investigations 

 (see Appendix), and international action has been taken 

 to endeavour to limit its ravages and if possible stamp it 

 out. It would appear that the disease has only attained 

 its present prominence in Africa comparatively recently, 

 coincident with the opening up of Africa to develop- 

 ment, consequently necessitating the formation of trade 

 routes and the movement of large bodies of natives from 

 point to point. The disease, if it existed amongst the 

 natives in earlier times, remained confined to circum- 

 scribed areas ; in opening up trade, however, the 

 disease diffused itself, and is still doing so, until it is 

 said to extend over some million square miles. The 

 spread of this disease has wiped out entire communities, 

 large districts have been depopulated in the Congo, 

 200,000 of the inhabitants of the Uganda Protectorate 

 are believed to have perished. 



The question naturally arises, How does the disease 

 spread ? Is it by contact, by water and food, or by 

 insects ? Knowing as much as we now do about the 



