SPIRILLUM OBERMEIERI 

 (RELAPSING FEVER) 



IN 1873 Obermeier discovered in the blood of those 

 suffering from Relapsing Fever an actively motile, 

 long, and very fine spirillum (Fig. 93). The organ- 

 ism is flexible, has finely-pointed extremities, and 

 measures some 16 to 40 /i in length. It is stained 

 with some difficulty by fuchsine and alkaline methy- 

 lene blue. It is found only in the blood and only 

 during the febrile attacks, and increases in numbers 

 up to the crisis. It has not yet been cultivated. 



Koch and Carter have succeeded in producing a 

 febrile disease in monkeys by the inoculation of 

 blood containing the spirillum, and the blood of 

 these inoculated animals also contains the spirillum. 

 Relapses are, however, not produced in these ani- 

 mals, which recover after a single attack of fever. 

 They are not rendered immune by the inoculation. 



