APPENDIX E. 



TRYPANOSOMIASIS KALA-AZARPIROPLASMOSIS. 



THE PATHOGENIC TRYPANOSOMES. 



THE trypanosomata are protozoal organisms belonging to the 

 sub-class Flagellata, and during the last decade several members 

 of the genus have come to be recognised as living in the blood 

 and tissues in various animals and as causing important disease 

 conditions. As long ago as 1878 the Trypanosoma Leivisi was 

 observed infesting the blood of rats, and it has been found to be 

 sometimes capable of causing death. Other diseases in which 

 similar organisms have been found are Surra, which occurs in 

 cattle, horses, and camels in India, and which is associated with 

 the Tr. Evansi ; Dourine, a condition affecting horses in especially 

 the Mediterranean littoral (Tr. equiperdum or Rougeti) ; Mai de 

 Caderas, a disease of South American horses (Tr. equinum or 

 Elmassiani) ; Tse-tse Fly Disease or Nagana, affecting horses 

 and herbivora in South Africa (Tr. Brucei) ; trypanosomiasis of 

 African cattle (Tr. Theileri) ; and most important from the 

 human standpoint the trypanosomiasis and sleeping sickness 

 of West and Central Africa associated with the Tr. gambiense 

 and Tr. ugandense, which are now believed to be the same 

 organism. These diseases present many general resemblances to 

 one another. They tend to be characterised by wasting, cachexia, 

 anaemia, fever often of an intermittent type and irregular oedemas, 

 and often lead to a fatal result. In many cases the infective 

 agent is conveyed from a diseased to a healthy animal by the 

 agency of blood-sucking insects. 



General Morphology of the Trypanosomata. If a drop of 

 blood containing trypanosomes be examined, the organism will 

 be seen to be a fusiform mass of protoplasm which at one end 

 passes into a pointed flagellum. In the living condition the 

 trypanosome is usually actively motile by an undulatory move- 



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