bejel vs syphilis

bejel

noun
  • Endemic syphilis, a chronic disease of skin and tissue caused by infection by a subspecies of the spirochete Treponema pallidum. 

syphilis

noun
  • A disease spread via sexual activity, caused by the bacterium Treponema pallidum. 

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