bubonic plague vs septicemia

bubonic plague

noun
  • A contagious, often fatal, epidemic disease caused by the bacterium Yersinia pestis, transmitted by the bite of fleas from an infected person or rodent, especially a rat, and characterized by delirium, chills, fever, vomiting, diarrhea, and the formation of buboes. 

septicemia

noun
  • A disease caused by the presence of pathogenic organisms, especially bacteria, or their toxins, in the bloodstream, characterised by chills and fever. 

How often have the words bubonic plague and septicemia occurred in a corpus of books? (source: Google Ngram Viewer )