DISEASES CAUSED BY SPIROCHETES 



601 



small piece of sterile rabbit kidney or testicle and a bit of the testicle of a 

 syphilitic rabbit, in which many spirochsetes were present. The fluid 

 was then covered with sterile parafHn oil and placed in an anaerobic jar. 

 After 10 days at 33.5° C. the spirochsetes had multiplied considerably, in 

 all but one case, together with bacteria. He obtained pure cultures 

 from these initial cultivations after much difficulty, by a number of 

 methods. At first he succeeded only by allowing the spirochsetes to 

 grow through Berkefeld filters, which they did on the fifth day. A 

 better method more recently adopted by him consists in preparing 

 high tubes of three parts of very shghtly alkaline or neutral agar to which 

 a piece of sterile tissue has been added. These tubes are then in- 

 oculated from the impure cultures with a long pipette. Close to the 







Fig. 131. — Spiroch^ta pallida. Liver, congenital syphilis. 

 (Levaditi method.) 



tissue and along the stab the spirochsetes and bacteria will grow and, 

 after about ten days to two weeks, the spirochsetes will have wandered 

 away from the stab and will be visible as hazy colonies. They can 

 then be fished, after cutting the tubes, and directly transplanted to 

 other serum-agar-tissue tubes prepared as before, and eventually will 

 grow in pure culture. By this method Noguchi has also cultivated 

 pure cultures from lesions in monkeys, and has produced lesions both in 

 rabbits and monkeys with his pure cultures. He has thus for the first 

 time carried out Koch's postulates with syphilis and established beyond 

 the shadow of a doubt the etiological significance of Spirochseta pallida 

 in syphihs. 



Animal Pathogenicity.^ — Until very recently, all experimental inocu- 

 lation of animals was unsuccessful. During the year 1903 Metchnikoff 

 and Roux"^ finally succeeded in transmitting the disease to monkeys. 

 The monkey first used by these observers was a female chimpanzee. 

 At the point of inoculation, the clitoris, there appeared, twenty-six days 



^Metchnikof et Roux, Ann. de I'lnst. Pasteur, 1903, 1904, and 1905. 



