bedbug vs vermin

bedbug

noun
  • A small nocturnal insect (Cimex lectularius), of the family Cimicidae, that feeds on the blood of humans and other warm-blooded hosts. 

vermin

noun
  • Any one of various common types of small insects or animals which cause harm and annoyance. 

  • Animals that prey on game, such as foxes or weasels. 

  • Obnoxious, or mean and offensive person or people. 

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