INTRODUCTION 



It is admitted on all sides that the Bacillus pestis is the 

 real and essential cause of Oriental or bubonic plague, and 

 consequently that the presence of this microbe in any 

 material derived from a human or animal being denotes 

 the disease plague in such a being. It is likewise ad- 

 mitted that a patient, although exhibiting one or more 

 symptoms suspicious of the disease plague — e.g. fever 

 with swollen and inflamed subcutaneous lymph glands 

 in one or the other region of the body, cervical, axillary, 

 inguinal, or femoral, — need not necessarily be affected with 

 bubonic plague, notwithstanding that such person might 

 have been indirectly exposed to plague infection. Should, 

 however, in such swollen inflamed glands the B. pestis be 

 demonstrated, epidemiologists and physicians would accept 

 such a case unquestionably as true plague. It is obvious 

 that should this be the case the relation of such a patient 

 towards his surroundings would at once be vastly different 

 from that in which a negative bacteriological result showed 

 that the patient is not affected with that infectious disease, 

 but is suffering from some other malady not requiring 

 those stringent and costly measures that a case of plague 

 requires. 



No greater misfortune, from a public health point of 



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