elephantiasis vs scabies

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. 

scabies

noun
  • An infestation of parasitic mites, Sarcoptes scabiei, causing intense itching caused by the mites burrowing into the skin of humans and other animals. It is easily transmissible from human to human; secondary skin infection may occur. 

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