DIPHTHERIA 231 



therapeutic value is very small. In our discussion of the different 

 sera, we shall accordingly only afford a limited space to the latter, 

 and largely confine our attention to those possessing marked anti- 

 toxic properties, the discovery of which ranks as one of the most 

 important in the science of medicine. The sera which here enter 

 into consideration will be discussed under the heading of the diseases 

 against which they are directed. 



ANTITOXIC IMMUNIZATION. 



DIPHTHERIA. 



After Roux and Yersin had shown that the clinical picture of 

 diphtheria is due to the action of a soluble toxin which is secreted 

 by the corresponding organisms (1888), v. Behring found that 

 animals which have been immunized against diphtheria are thus 

 rendered resistant to the toxin in question, and that the blood of 

 such animals contains a principle which can be transferred to 

 other animals and can protect these against subsequent infection, 

 or cure this, as the case may be (1890). This principle he termed 

 antitoxin. 



The first attempt to apply this important discovery to the cure of 

 diphtheria in the human being was made in Berlin in v. Bergmann's 

 clinic (1891). The results, while suggestive, were not altogether 

 satisfactory, however, as the serum which was then available was 

 too weak and the dosage too small. But subsequent investigations 

 by a number of different observers, notably Roux, Ehrlich, Kossel 

 and Wassermann, Aronson and Baginsky, etc., supported v. Behring's 

 claims in their entirety and demonstrated conclusively that one of 

 the most fearful and most intractable diseases to which the human 

 being is subject had indeed been conquered. Since then diphtheria 

 antitoxin has been the means of saving untold thousands of lives 

 which otherwise would have been doomed, and has thus proved 

 one of the greatest blessings to the entire civilized world. 



While people still die of diphtheria at the present day, this is 

 largely owing to ignorance or indifference on the part of those to 

 whom the medical profession must, after all, look for the earliest 

 diagnosis of the disease, or at least for the recognition of those symp- 

 toms which should serve as danger signals, i. e., the parents and 



