herpes vs tabes dorsalis

herpes

noun
  • A viral infection, caused by Human alphaherpesvirus 1 and Human alphaherpesvirus 2, marked by painful, watery blisters in the skin or mucous membranes or on the genitals. 

tabes dorsalis

noun
  • neurosyphilis in the form of such degeneration. 

  • tabes of the back; a degeneration of the sensory neurons of the spinal cord carrying afferent information. 

How often have the words herpes and tabes dorsalis occurred in a corpus of books? (source: Google Ngram Viewer )