PAET II 

 CHAPTER XV 



SLEEPING SICKNESS, FLIES, AND DISEASE 



TRYPAXOSOMIASIS (SLEEPING SICKNESS) 



This morbid condition, better known in one of its forms 

 in man as sleeping sickness, belongs to tliat group 

 of diseases, including malaria, filariasis, and tick fever, 

 which are caused by minute animal parasites living 

 in the blood stream of the body. J^ike, also, many of 

 the other tropical diseases, it attacks a wide range of 

 the animal kingdom. I have had occasion to refer to 

 this significant fact before. We will have noted that 

 these diseases are not peculiar to man alone ; man is 

 simply liable to them just as are other species of the 

 animal kingdom. 



Naturally, when man is affected in epidemic form, 

 our attention is at once directed to the disease, and 

 investigations made and the cause discovered. It was 

 thus with sleeping sickness. 'J'he trypanosome, as the 

 small blood parasite which causes tlie disease is called, 

 was discovered in 1902, but long before tliat date 



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