CHAPTER X. 

 RELAPSING FEVER. 



As long ago as 1873, Obermeier discovered that a 

 flexible spiral organism, about o. i fj. in diameter and 

 from 20-40 fj. in length, could be observed in the blood 

 of patients suffering from relapsing fever. 



Although many of the best bacteriologists of our day 

 have occupied themselves with the study of this spiril- 

 lum, we really have, at present, very little more know- 

 ledge than that given us by Obermeier. 



FIG. 1 20. Spirochgeta febris recurrentis; x 650 (Heim). 



The spirilla (Fig. 120) are generally very numerous, 

 are long, slender, and flexible (spirochseta), and possess 

 a vigorous movement by flagella. The ends are rather 

 pointed. 



The spirillum stains well by ordinary methods, but 

 not by Gram's method. It seems to be a strict parasite, 

 and has never been cultivated artificially. 



Of the pathogenesis of the organism there can be no 

 doubt, as it is invariably present in relapsing fever and 



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