550 



PATHOGENIC SPIRILLA. 



In experiments made by Heydenreich the spirillum was found to 

 preserve its vitality (motility) for fourteen days at a temperature of 



Fio. 172. Spirillum Obermeieri in blood of man. x 1,000. From a photomicrograph. 

 (FrSnkel and Pf eiffer. ) 



16 to 22 0., for twenty hours at 37, and at 42.5 for two or three 

 hours only. 



Pathogenesis. Causes in man the disease known as relapsing 

 fever. Munch and Moczutkowsky have produced typical relapsing 



Fio. 173. Spirillum Obermeieri in blood of an inoculated ape. x 700. (Koch. 



fever in healthy persons by inoculating them with blood containing 

 the spirillum of Obermeier. The spirilla are found in the blood dur- 

 ing the febrile paroxysm, and for a day or two, at the outside, after 



