20 INFECTIOUS AND PARASITIC DISEASES. 



both cases the toxins play the same important role; 

 yet while in the one they are formed in only one portion 

 of the body, in the other, since the infectious agents 

 are scattered, they are formed in all parts. Infectious 

 diseases which result from toxins eliminated by micro- 

 organisms growing in a circumscribed area are known 

 as toxcemias, while those in which the micro-organisms 

 live and multiply in the blood-stream are called sep- 

 ticcEmias (in cases in which bacteria are the invaders, 

 bactericemias) . A general infection, therefore, corre- 

 sponds to a septicaemia, or bacteriaemia. It must not 

 be inferred, however, that a toxaemia always accom- 

 panies a local infection, for there are many local infec- 

 tions in which the action of the agents and their toxins 

 are purely local; the word toxaemia is reserved for local 

 infections associated with constitutional symptoms of 

 poisoning. To illustrate : No one would call an abscess 

 an infectious disease, although it represents the localized 

 activity of certain bacteria, and is therefore correctly 

 spoken of as a local infection. On the other hand, 

 tetanus, a constitutional disease, has as its local infection 

 a wound, frequently so trivial, that it has healed before 

 the convulsions begin which mark the onset of this 

 terrible disease. It is the toxins formed by the bacilli 

 at one point, and absorbed, which give rise to the 

 toxaemia. 



A local, or a general infection, may be caused by either 

 a specific or a non-specific infectious agent, but not by 



