SYPHILIS 503 



4>ecies of the laboratory animals than the sp. Obermeieri. The 

 most important differences are however brought out by immunity 

 reactions. It was shown by Breinl that the immunity produced 

 by the sp. Obermeieri did not protect against the sp. Duttoni, 

 and that the converse also held good ; and it has since been 

 established that a similar difference obtains between the sp. 

 Duttoni and the organisms of the Asiatic and American varieties 

 of relapsing fever. Corresponding results are obtained on 

 testing the various serum reactions in vitro. 



Levaditi has succeeded in obtaining cultures of the spirochsete 

 of tick fever by inoculating sacs filled with monkey's serum, 

 heated at 70 C., and placing the sacs in the peritoneal cavity of 

 a rat or rabbit ; when opened at the end of five to seven days, 

 the sacs were found to contain an abundant growth of spiro- 

 chaetes, some of which were of unusually great length. Growth 

 was maintained in similar sub-cultures, and the virulence was 

 well preserved. 



SYPHILIS, 



Up till quite recent times practically nothing of a definite 

 nature was known regarding the etiology of syphilis. Most 

 interest for a long time centred around the observations of 

 Lustgarten, who in 1884 described a characteristic bacillus, 

 both in the primary sore and in the lesions in internal organs. 

 This organism occurred in the form of slender rods, straight, or 

 slightly bent, 3 to 4 /u, in length, often forming little clusters 

 either within cells or lying free in the lymphatic spaces ; it took 

 up basic aniline dyes with some difficulty, but was much more 

 easily decolorised by acids than the tubercle bacillus. The 

 etiological relationship of the organism to the disease was, 

 however, not generally accepted, and in view of the recent work 

 on syphilis, the organism cannot be regarded as having any 

 pathological importance. 



Spirochaete pallida. An entirely new light has been thrown 

 on the etiology of the disease by the work of Schaudinn and 

 Hoffmann which appeared in 1905. Since their first publication 

 a great amount of work has been undertaken in order to test 

 their conclusions, and the results have been of a confirmatory 

 nature. These observers found in cases of syphilis an organism 

 to which they gave the name spirochcete pallida ; it now also 

 goes by the name spironema pallidum. As described by them, 

 it is a minute spiral-shaped organism, showing usually from six 

 to eight curves, though longer forms are met with ; the curves 



