mange vs scabies

mange

noun
  • A skin disease of nonhuman mammals caused by parasitic mites (Sarcoptes spp., Demodecidae spp.). 

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 mange and scabies occurred in a corpus of books? (source: Google Ngram Viewer )