RELAPSING FEVER ORGANISM 221 



arborescent colonies. These can be selected pure by cutting the 

 tube and the agar column. Motion is of screw and serpentine 

 character. No odor or spores are produced. This organism must 

 be imagined and remembered as a corkscrew and not a waving line. 

 The Gram stain is negative. 



The Spiroch&ta refringens, which has been also cultivated by 

 Noguchi and thought by him to be a Treponema also, grows without 

 fresh animal tissue in a short time and produces no odor. 



Pathogenesis. It has been found in chancre, condylomata, and 

 mucous patches in the early stages of syphilis; also in the blood, 

 blister-fluids, spleen, bone marrow, liver, thymus gland, and lym- 

 phatic glands. Investigators claim that it exists in smegma and 

 other foul secretions, but this has not been confirmed. Associated 

 with this organism, in nearly every case, is a coarser looking larger 

 spirochaete (Treponema), which stains deeper, and has been called 

 the Spirochaeta (Treponema) refringens. 



In a series of experiments, Metchnikoff and Roux caused abortion 

 of the chancre following inoculation of syphilitic virus on the eyelid 

 of a chimpanzee, by calomel inunction carried out less than one hour 

 after the infection; a solution of sublimate has not the same pro- 

 phylactic property. 



It does not require any intermediate host for transmission as do 

 the recognized animal parasites of malaria and filariasis, etc. 



RELAPSING FEVER ORGANISM. 



European Relapsing Fever.' Caused by Spirochaeta obermeieri, 

 transmission not exactly known. 



African Relapsing Fever.' Caused by Sp. duttoni, transmitted 

 by tick Ornithodorus moubata. 



American Relapsing Fever. Caused by Sp. Novii, transmission 

 not known. 



Bombay Relapsing Fever. Caused by Sp. carter!, transmission 

 not known. 



