558 



TRYPANOSOMES AND TRYPANOSOMIASES 



FIG. 191 



anatomic changes specifically characteristic for trypanosomiases ; 

 enlargement of the spleen and the lymphatics, however, is frequently 

 present. When an infected animal is nearing a fatal termination 

 the trypanosomes seen in the blood are usually less mobile and more 

 granular than they are under other conditions. 



Diseases Due to Pathogenic Trypanosomes. The most important 



diseases of animals and man due to trypanosomes are the following: 



Surra. This disease is due to the Trypanosoma Evansii, and 



attacks horses and cattle, water buffaloes and carabaos in India, 



China, the Philippine Islands, and other Asiatic countries. 



Nagana. This disease is due to Trypanosoma Brucei, and is 

 prevalent in Africa, among horses, cattle, camels, wild buffaloes, 



antelope, wildepests, and prob- 

 ably also elephants. It is in- 

 variably fatal in the equidae 

 and dog, but may terminate in 

 recovery and immunity in cattle. 

 Allied to nagana are a number 

 of other trypanosomiases in 

 various parts of Africa described 

 by Koch (German East Africa), 

 Theiler (Transvaal), Brumpt 

 (Ogaden), Schilling, Ziemann 

 and Martini (Togo), Button and 

 Todd (Gambia), and Broden 

 (Congo). Some of these infec- 

 tions are probably identical with 

 nagana, while others are due 

 not to the Trypanosoma Brucei, 

 but to different distinct species. 

 Of the latter the best known is 



a disease of bovidae of South Africa described by Theiler under the 

 name of gall sickness, or galziekte. It is due to a trypanosome first 

 fully described by Laveran, and named in honor of its discoverer 

 Trypanosoma Theileri. 



Coder as, or Mai de Caveras. This is the trypanosomiasis (Try- 

 panosoma equinum) of horses in South Africa, first discovered by 

 Voges. . 



Dourine. A somewhat peculiar position among the trypanoso- 

 miases is held by dourine, or mal du coit (Trypanosoma equiperdum), 

 of the equidse, a disease transmitted directly from individual to indi- 

 vidual by sexual intercourse. It is the only pathogenic trypanosome 

 infection of domesticated animals occurring in European countries, 

 such as Spain, France, Germany, Switzerland, Austria, Hungary, 

 Turkey, and the Balkan States. The trypanosome of dourine was first 

 seen in 1894 by Rouget, and the presence of these parasites in this 

 affection was later established beyond doubt by the researches of 



Trypanosoma gambiense in human blood, 

 cause of sleeping sickness in man. X 1000. 

 (Author's preparation.) 



