382 INFECTION AND IMMUNITY. 



immune there is a normal small,, raised, inflam- 

 matory., itching, hyperemic area. 



"Is the one previously inoculated, therefore, 

 hypersusceptible ? If we wait a few days the 

 picture changes: The papule becomes brownish 

 and smaller, while in the case of the first vaccina- 

 tion, a vesicle forms under the crust, which in- 

 creases more and more, becomes surrounded by a 

 wide zone, and leads to a pustule. Now we must 

 conclude that the one receiving his first inocu- 

 lation is the more susceptible, since he has fever, 

 pain, and a marked local inflammation, while in 

 the immune person signs of infection have long- 

 since disappeared. 



"As it appears to me both individuals have 

 reacted: The one earlier, the other later; one 

 with a papule, the other with a pustule. In one 

 the reaction was hardly noticeable, in the other 

 pronounced. Through the previous inoculation 

 no immunity in the sense of insusceptibility has 

 developed, but it is only the ability to react which 

 has changed, and this in point of time, quality, 

 and quantity/' 



The condition then appears to be a paradoxical 

 one, in that we have a certain degree of hyper- 

 susceptibility in a person who is really immune 

 and his immunity may depend to a greater or 

 less degree on his ability to react quickly to the 

 presence of the infectious agent before the latter 

 has time to proliferate extensively. 



Portier and Eichet, in 1902, observed a peculiar 

 behavior on the part of a poison found in certain 

 actinia. 



