368 APPLICATION OF METHODS OF BACTERIOLOGY 



ing degrees the blood serum of such immunized animals 

 has both a curative and a prophylactic influence upon the 

 course of streptococcus infection in human beings. 



The method of producing the antiserum is, in general, 

 to inject gradually increasing doses of virulent Streptococcus 

 pyogenes (beginning with dead cultures)- into the tissues 

 of the animal until its blood serum is found to have an 

 inhibiting effect upon experimentally produced streptococcus 

 infection in test animals. 



Reports upon the therapeutic use of antistreptococcus 

 serum in a variety of streptococcus infections are dis- 

 cordant; some authors being enthusiastic as to its curative 

 value, others skeptical or actually denying to it such virtues. 

 The reasons for these divergent opinions are now pretty 

 manifest from what has been said under the preceding 

 heading "Variations in Streptococci." 



THE LESS COMMON PYOGENIC ORGANISMS. 



The organisms that have just been described are com- 

 monly known as the "pyogenic cocci" of Ogston, Rosenbach, 

 and Passet, and up to as late as 1885 were believed to be the 

 specific factors concerned in the production of suppurative 

 inflammations. Since that time, however, there has been 

 considerable modification of this view, and while they are 

 still known to be the most common causes of suppuration, 

 they are also known to be not the only causes of this phe- 

 nomenon. 



With the more general application of bacteriological 

 methods to the study of the manifold conditions coming 

 under the eye of the physician, the surgeon, and the patholo- 

 gist, observations are constantly being made that do not 



