PATHOGENIC PROTOZOA OF THE MASTIGOPHORA 



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and a vacuole appears at one side of the blepharoplast, and from 

 this a single flagellum develops. The body finally assumes an 

 elongated form not unlike a trypanosome, without an undulating 

 membrane. This is the Herpetomonas stage. This may now 

 divide longitudinally, frequently unequally, splitting off very 

 slender cells. The systematic position of this organism is still 

 somewhat in doubt. It may be that it should be regarded as 

 belonging to a distinct genus, and the name Leishmania used 

 instead of Herpetomonas. 



Pathogenesis. The disease is characterized by enlargement 

 of the spleen and by fever. 



Transmission. It is believed that the parasite is transferred 

 from the dog to man through some intermediate host. 



Leishmania (Herpetomonas ?) infantum 



Xicolle has described an organism similar to the preceding 

 from a disease which he calls infantile kala-azar. The organisms 



Fig. 192. Herpetomonas infantum: A, Organisms from the spleen of a child; 

 B, a mononuclear containing the organisms, and C, an endothelial cell from the 

 spleen; D, various stages in the development of the Herpetomonas form from 

 the Leishman-Donovan bodies (Nicolle). 



resemble the preceding, but are believed to constitute a separate 

 species. The disease is primarily one of dogs, which may be 

 transmitted to children. 



Leishmania tropica 



Synonyms. Ovoplasma orientale: Helcosoma tropicum. 



Wright has described a similar organism as the cause of oriental 

 sore or Delhi boil in man. It is probably transmitted likewise by 

 some biting insect. The dog may be infected and show clinical 

 symptoms similar to man. 



