rick·ett·sia /rɪˈkɛtsiə/
  發疹傷寒等的病原體
  rick·ett·sia /rɪˈkɛtsɪə/ 名詞
  (複rickettsiae)立克次體
  Rickettsia
       n : any of a group of parasitic bacteria that live in arthropods
           (as ticks and mites) and can cause disease if transmitted
           to human beings