t6o manual of bacteriology. 



bacterial products from a localized point of invasion, and their 

 dissemination throughout the body by means of the circulation. 

 We see typical toxemias in diphtheria and tetanus. In surgery 

 the term sapremia is used to cover a similar condition of affairs 

 when the absorption proceeds from a wound or denuded sur- 

 face, as may happen in the puerperal uterus. 



Septicemia. — In septicemia there is not only absorption 

 of bacterial poisons, but the bacteria have invaded the living 

 tissues and the blood (though not producing metastatic ab- 

 scesses). Bacteriologists usually employ the word septicemia 

 to describe the wide dissemination of bacteria through the body 

 and the presence of a large number of them in the circulating 

 blood. In this sense septicemias are less common in man 

 than in such diseases as anthrax in the lower animals. Typical 

 septicemias in man are found in relapsing fever and certain 

 cases of bubonic plague. For pyemia, see the article on Sup- 

 puration, Part IV. 



The principal agencies in effecting recovery from infectious 

 diseases are the destruction of the bacteria by the cells of the 

 body (phagocytosis), the development of new substances which 

 neutralize their action (antitoxins) and the presence or for- 

 mation in the body of substances which destroy bacteria (lysins). 

 These phenomena are discussed in the chapter on Immunity. A 

 factor of less importance is the elimination of bacteria by the 

 excretory organs. Investigators who have made experiments 

 on animals disagree as to whether or not the bacteria which 

 have been injected into the body appear in the urine before they 

 have damaged the structure of the kidney. In typhoid fever, 

 the bacilli of typhoid may occur in the urine in great numbers ; 

 the condition of the kidney in the generality of such cases has 

 not thus far been determined. The extent to which the ex- 

 cretory organs act in eliminating bacterial toxins is not yet 

 known. Some bacteria, as has already been stated, may, in the 

 end, produce substances that are inimical to their own growth. 



