The Protozoa 



147 



^i^H 



Trichomonas hominis (Fig. 60). 

 Cercomonas hominis. 



In intestines, causing acute or chronic diarrhea. 

 Lamblia intestinalis. 



Larger than the trichomonas. Flagellated forms have been 

 found in the sputum of cases of gangrene of lung, and in those having 



pleurisy. 



Borrelia recurrentis (formerly Spirochaeta recurrentis). (Fig. 



61.) , 



Causes Relapsing Fever 



(also called Famine Fever, Seven 

 Day Fever, and Tick Fever), prob- 

 ably transmitted by mosquitoes or 

 bugs. From five to seven relapses 

 take place after all symptoms have 

 disappeared. 



The spirillum or spirochete 

 is 15 to 40 micra long, shaped like 

 a corkscrew. Quite motile and 

 present in blood during the febrile 



paroxysms, disappearing at intervals. 



The disease has been reproduced by injecting into a healthy 



monkey the blood sucked by a bug from an infected animal. 



* 



1. Borrelia recurrentis, found in Russia. 



2. Same as 1, but from a patient in Africa. 

 (From Kolle-Wassermann.) 



d/v\A/WV 



e MW^ 



jv\a 



Fig. 62. 



Schematic drawing of undulating membrane of Spirochaetes. a and b Spiro- 

 chaeta pallida; c, S. refringens ; d, a small Spirochaete of the same species; 

 e, Spirochaete found in an ulcerated carcinoma; f, Spirochaete dentium; g, Spi- 

 rochaeta plicatilis merely showing the extremity of a rather long individual. 

 (After Schaudinn.) 



Treponema Pallidum (Fig. 62). 



Cause of syphilis. 



Acquired syphilis is due to a mucous membrane coming in 

 contact with the spirochete. 



Congenital syphilis is transmitted through the mother to the 

 child. 



The treponema is a spiral, curved organism from five to fifteen 

 microns in length, showing active movements in fresh specimens. 



