RELAPSING FEVER 



149 



diphtheria (1884), tetanus (1884), influenza (1892), 

 bubonic plague (1894), dysentery (1900). 



This germ is a slender spiral filament, which is 

 found in the blood of relapsing-fever patients during 

 the febrile paroxysm. The presence of the spirillum 

 in the excreta of relapsing-fever patients has not 

 been demonstrated, but it can scarcely be doubted 



FIG. 4. Spirillum of relapsing fever, as seen in the blood ; magnified 1000 

 diameters. 



that this disease belongs in the same category with 

 typhoid fever, bubonic plague, and Asiatic cholera 

 i. e., that it is one of the filth diseases and is spread 

 principally by means of excreta containing the spe- 

 cific infectious agent or germ. It may be that the 

 spirillum of relapsing fever produces reproductive 

 spores, which would be difficult of demonstration in 



