acquired immune deficiency syndrome vs tabes dorsalis

acquired immune deficiency syndrome

noun
  • An infectious disease, caused by HIV, that causes the gradual degeneration of the body's immune system. 

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 acquired immune deficiency syndrome and tabes dorsalis occurred in a corpus of books? (source: Google Ngram Viewer )