HUMAN SPIROCHETES 



443 



L HUMAN SPIROCHETES. 



A. Blood Spirochetes. 



Spiroschaudinnia recurrentis Lebert, 1874. 



Synonyms. — Spirochcete recurrentis Lebert, 1874; S. ohermeyeri 

 Cohn, 1875. 



This spirochaete Was discovered by Obermeyer in cases of relapsing 

 fever in Berlin. 



Morphology. — -It exists in the blood in short and long forms. 

 The short forms, which are from 7 to 9 in length, are probably 

 early stages. The long forms, 16 to 19 ^, result from multiplica- 

 tion or agglutination. The latter condition in a hyperimmune blood 

 may lead to forms 18 to 100 in length, brought about by agglutina- 

 tion of two or more cells end to end. The width is 0-25 fji. The 

 number of spirals in the short 

 form, which is considered to be 

 one cell, is two to three. 



The short form is said by 

 Novy and Knapp to have a 

 long flagellum at one ead, 

 while the other has a faint 

 appendage. The presence of 

 fiagella in this as Well as in 

 other spirochetes is denied by 

 Nuttall. 



Life-History. — ■ This spiro- 

 chaete is pathogenic to man, 

 monkeys, rats, and mice; but 

 these latter have to be infected 

 firom a monkey. Rabbits or 

 guinea-pigs are not susceptible. 

 It is found in the peripheral 

 blood during the attacks and 

 relapses, but not in the inter- 

 mission, unless occasionally 

 after very protracted search. It can also live in the bed-bug — • 

 Clinocoris lectularius — -for some days, and Nuttall has succeeded on 

 one occasion in transmitting 5. recurrentis from mouse to mouse 

 by the bites of the same bug. Positive results have also been 

 obtained by Sikul in Odessa. Most authorities consider lice to be 

 the carriers. 



Immunity. — -The blood serum of animals immunized to S. recur- 

 rentis is without effect upon 5. duttoni and 5. novyi. 

 Pathogenicity. — It is the cause of European relapsing fever. 



Fig. 132. — Spiroschaudinnia from a 

 Case of Asiatic Relapsing Fever. 



(From a raicrophotograph by 

 J. J. Bell.) 



