250 CHE MO THERA P Y 



fast strains can exist, and we accordingly find that after a patient 

 has safely passed through the two or three corresponding relapses, 

 spontaneous recovery occurs, there being then antibodies present 

 against the only strains that are possible in that particular milieu. 

 In syphilis, it is quite different. Here the number of foodstuffs that 

 the spirochete can utilize is evidently quite large. In the untreated 

 individual, relapse follows relapse, and the damage done to vital 

 parts is only too often so extensive, relatively early in the course 

 of the infection, that the patient succumbs, owing to the resultant 

 injury, long before the disease has "worn itself out." 



The discovery of this element of "fastness" or resistance on the 

 part of microorganisms, is evidently of the greatest importance, as 

 it throws light upon many phenomena, the cause of which has here- 

 tofore been most obscure. The question has thus long remained 

 unanswered, why the syphilitic individual cannot be reinoculated 

 with syphilitic virus while his disease is active. The reason now is 

 quite evident. For we know that the spirochetal strains which at 

 any times are operative in the body of the syphilitic patient are 

 "fast" strains, of varying degree, and that antibodies are present 

 in his blood which are specifically "tuned" to those of a lower 

 order, i. e., to those serum strains from which the "highest" ones 

 have become developed, so that the "street spirochete" so to speak, 

 if introduced under such conditions, must of necessity meet with 

 those antibodies which would lead to their destruction. If once it 

 were possible to cultivate all these different strains, then it would 

 also be possible to reinfect the syphilitic individual, not with the 

 street virus to be sure, but with a strain of a higher order of serum 

 fastness, that would correspond to the number of antibodies that 

 have already been formed. In the animal experiment, using 

 trypanosomes, this can indeed be done at the present time, and 

 at the Speyer Haus, in Frankfurt, Ehrlich has under cultivation 

 all five of the possible serum-fast strains which are possible in the 

 organism of the mouse. 



Therapia Magna Sterilisans. As the development of "fast" strains 

 is thus one of the greatest impediments to the successful treatment 

 of the maladies in question, our efforts should be directed to the 

 discovery of medicinal substances which should be capable of effect- 

 ing the complete sterilization of the individual at one time (Ehrlich's 

 therapia magna sterilisans). The demonstration that this is actually 



