306 SYMBIOGENESIS 



It must be noted that in certain instances a first injection of horse 

 serum is quite capable of inducing such symptoms as urticaria, arthritis, 

 nausea, vomiting, oedema, pruritus. It has even been stated that normal 

 horse serum, the serum of horses not immunised with diphtheritic toxin, 

 can produce symptoms in predisposed individuals. 



It is thus clear that some persons are already predisposed 

 by an in-feeding diathesis (equivalent to a latent anaphylactic 

 state, as I should interpret this to be) to anaphylactic shock. 

 Indeed, some such explanation seems to sugge'st itself to Prof. 

 Richet, as the following passage bears out : 



It may therefore be asked if there is not such a condition as spon- 

 taneous, natural, or idiosyncratic anaphylaxis. But the word idiosyn- 

 crasy explains nothing; it would be better to suppose that there was 

 such a condition as special anaphylaxis induced by diet. This would 

 practically account for the fact that symptoms invariably follow the 

 first injection of horse serum into those who, for therapeutic purposes, 

 take a raw horse-flesh diet. (Unpublished work, de Rist and Ch. Richet, 

 junior.) Certainly some individuals who have never eaten raw horse 

 flesh are sensitive to a first injection of horse serum; but the more or 

 less rigorously specific limits of the anaphylactising antigen have not 

 yet been so defined as to enable us to say that there were not in their 

 diet substances capable of developing a special anaphylactic state against 

 horse serum. Therefore, this statement, which has been formally made, 

 appears to us of very great importance in proving that an undoubted 

 anaphylactic state to horse serum can be induced by horse-flesh diet. 

 (Italics mine.) 



Prof. Richet thus tells us in other words that in-feeding 

 generally may easily result in liability to serum-disease, which 

 merely becomes more acute upon a single injection of the serum 

 of the particular animal the flesh of which has been consumed. 



I fully concur with Prof. Richet in supposing that there 

 is such a condition as " natural " anaphylaxis induced by diet, 

 although I believe I have termed this condition with more 

 accuracy and biological justification a "parasitic diathesis." 



Some anaphylaxis investigators have coined the term 

 allergy to mark the phenomenon of reaction of an organism to a 

 foreign substance. It remains then to tabulate all disease in 

 terms of "allergy." 



