elephantiasis vs leprosity

elephantiasis

noun
  • A complication of chronic filariasis, in which nematode worms block the lymphatic vessels, usually in the legs or scrotum, causing extreme enlargement of the infected area. 

leprosity

noun
  • The supposed impurity or impurities of various metals, understood as causing their deviation from gold. 

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