234 MECHANISM OF INFECTION AND IMMUNITY 



Many years ago Gamaleia showed that fever follows the parenteral 

 introduction of dead as well as living bacteria, either pathogenic or 

 non-pathogenic. He concluded that fever is not a phenomenon of 

 bacterial growth in the body. Furthermore, he found that the less 

 virulent the organism, the higher and more persistent is the fever. A 

 rabbit inoculated with the anthrax bacillus suffers a fever for only a 

 few hours, when the temperature falls and death results, while one 

 inoculated with a highly attenuated anthrax culture (the second vac- 

 cine) shows fever for three days and then recovers. With a highly 

 virulent culture, there may be but little or no elevation of temperature 

 and death comes within from five to seven hours after inoculation. 

 The febrile process is not a result of the activity of the bacteria, but, 

 on the contrary, is due to a reaction of the body against their presence 

 and marks their destruction. 



More recently it was shown by experiments in my laboratory that 

 fever can be induced in animals by the subcutaneous injection of pro- 

 teins of diverse origin and structure, and that by modifying the size 

 and frequency of the dose, the type of fever can be determined at will. 

 By injecting egg-white into rabbits and by regulating the size and 

 interval between doses, one may induce an intermittent, remittent, 

 continued or acute fever. In the last mentioned, the temperature can 

 be carried to 107 F. with a fatal termination. Not only fever but 

 its accompaniments also may be developed. In the continued fever 

 thus induced, there is the morning fall and the evening rise so con- 

 stantly seen in typhoid. There is loss of appetite with lassitude, 

 gradual emaciation, decreased urinary output and increased nitrogen 

 elimination. Protein fever, which includes all infective and practically 

 all clinical fevers, results from parenteral digestion. In this process 

 the animals' cells supply the ferment and the foreign protein constitutes 

 the substrate. The foreign protein may enter the body living or dead, 

 with or without form. It may be detached and dead tissue from 

 the animal's body, as after burns. It may be absorbed from some 

 mucous surface, as in hay fever. It may be artificially introduced, 

 as in serum disease. It is usually a living protein, as in the infectious 

 diseases. 



There are other causes of fever, but that of the infectious diseases 

 results from the parenteral digestion of the infecting agent by specific 



