298 CLINICAL BACTERIOLOGY. 



the immunity lasting for more than eight months. In this 

 way would be demonstrated the law for anthrax that Colles 

 propounded for syphilis (p. 318). 



Bacteriologic Diagnosis. From the deeper parts of a 

 suspected pustule some tissue-fluid is removed and plates 

 are made therefrom. If suspicious colonies develop, pure 

 cultures are made and animals infected therewith. If intes- 

 tinal anthrax is suspected, the vomited matters and the feces 

 should be examined bacteriologically. In cases of pulmon- 

 ary anthrax the abundant frothy sputum at times contains 

 the bacilli. Examination of the blood will yield informa- 

 tion as to whether general infection with anthrax is present 

 or not. Such examination is, therefore, always of the 

 greatest importance in the formulation of the prognosis. It 

 must, however, always be borne in mind that the bacilli are 

 present especially in the capillary area. 



For sanitary purposes it is frequently necessary to decide 

 whether an animal has died of anthrax or not. If death 

 has taken place but a short time previously, microscopic 

 examination of fluid from the spleen and of the blood will 

 suffice. The presence of the bacilli with capsules, demon- 

 strable by the method of Johne (p. 288), renders the diag- 

 nosis positive. If, however, one or more days have elapsed 

 since the death of the animal, then there develop in the body 

 of animals dead of anthrax cadaver-bacilli that can be dif- 

 ferentiated from the specific exciting agents of anthrax only 

 with exceeding difficulty. Under such conditions gelatin- 

 plates must be made, and mice and guinea-pigs inoculated 

 with fluid from the spleen. 



In inoculating the animals the possibility of the presence 

 of the bacillus of malignant edema must be borne in 

 mind, as this microorganism likewise is not rarely found 

 in the bodies of dead animals. On subcutaneous in- 

 oculation the latter predominates, and the animals die of 

 malignant edema notwithstanding the presence of anthrax- 

 bacilli. This source of error can be avoided by inoculat- 

 ing the animals cutaneously with the suspected material. 

 The anthrax-bacillus alone will then develop, and the 

 diagnosis can not go astray. If putrefaction has pro- 

 gressed too far in the body to be examined, then the 

 anthrax-bacilli may be completely suppressed by the com- 

 petition of the other varieties of bacteria, so that the diag- 

 nosis is no longer possible. 



