THE CONQUEST OF DISEASE 



A small quantity of human blood, containing 

 the parasite, injected into an animal, causes the 

 disease and death; and the same pathologic 

 changes are found as occur in the brain of man. 



The discovery by Forde in 1901 of a peculiar 

 wormlike, active body in the blood of a patient 

 suffering from an "African fever" stimulated 

 research. These organisms were repeatedly 

 found and named by Dutton Trypanosoma 

 gambiense. Dutton and Todd in 1902, work- 

 ing under the auspices of the Liverpool School 

 of Tropical Medicine, discovered the relation 

 of these parasites to trypanosomatic fever in 

 man. Then Castillani discovered the same 

 organism in the cerebro-spinal fluid of a victim 

 of sleeping sickness. This led to the discovery 

 by Bruce and others that trypanosomatic 

 fever is simply the first stage of sleeping sick- 

 ness. In 1903 Bruce announced that sleeping 

 sickness is due to the introduction of an animal 

 parasite into the human blood through the 

 agency of the tsetse fly. These discoveries 

 have all been confirmed ; and the organisms can 

 easily be found in the blood of any case of this 

 disease. 



The disease was making such frightful 

 ravage in Africa that Dr. Koch of Berlin, the 



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