258 



INFECTIVE DISEASES. 



recovery, and in about fourteen days by another, attack of fever, 

 which maiy be repeated after another week. 



Starvation, in association with overcrowding and filth, is intimately 

 connected with the causation of the disease. The subjects of the 

 disease contaminate the air around them, and the virus is principally 

 conveyed by tramps and dirty people. 



Obermeier discovered spirilla in the blood during the paroxysms 

 of fever. The constant occurrence of the spirillum in relapsing 

 fever, and the fact of its not being found in any other conditions, 

 render it very probable that it is the cause of the disease. 





Fig. 124. — Spieillum Obermeieei in BtooD OB' Monkey Inoculatkd with 

 Spirilla aptee Removal of the Spleen (Soudakewitch). 



Spirillum Otaermeieri [Spirochceta Obermeieri, Cohn). — 

 Threads similar to the Spirillum plicatile. In length they are mostly 

 16 to 40 fj,, with regular screw-curves. They move very rapidly, 

 and exhibit peculiar wave-Uke undulations. They are absent from 

 the blood during the non-febrUe intervals, but are found in the 

 interior of leucocytes in the spleen. In blood serum and 50 per 

 cent, salt solution, they preserve their movements. In cover-glass 

 preparations they are readily stained by any of the aniline dyes, 

 and in sections, by preference, with Bismarck brown. They are not 



