162 



ANAPHYLAXIS IN ITS RELATION TO DISEASE 



But, whereas the injection of horse serum does not necessarily give 

 rise to any symptoms during this time, since the material that is 

 introduced is sterile, vaccination is early followed by certain local 

 symptoms which we may logically attribute to a multiplication of 

 the organism of cowpox in the skin. This is shown diagrammatically 

 in Fig. 5 in the gradually ascending line representing the first vac- 

 cination. We may then suppose that the absorption of some dead 

 organisms (dead when introduced or destroyed by the local defen- 

 sive forces shortly after their introduction), i. e., of their proteins, 



FIG. 5 



Days } l ...... ,8 



15 



Injection of 

 larger quantity 

 of Vaccine 



Incubation 

 period 



Intense local and 

 general reaction 



Diagram illustrating the effect of vaccination in its relation to antibody formation upon the 

 development of the corresponding clinical symptoms. (Taken from v. Pirquet.) 



is followed after the usual period of about eight days by the pro- 

 duction of the corresponding antibodies, some of which, no doubt, 

 bring about the destruction of all the remaining organisms, while 

 others react with the liberated proteins and give rise to anaphylatoxins 

 which in turn are responsible for the rapidly developing local inflam- 

 matory reaction, as also perhaps for some of the systemic symptoms. 

 Theoretically, of course, the anaphylactic response should continue 

 so long as both antigen and antibody are present, a conclusion with 

 which clinical observation is in perfect accord. It might, of course, 

 be argued that the period of incubation following vaccination was 

 after all due to the multiplication of the variola organisms, and that 

 so soon as this had exceeded a certain point, the local as well as the 



