Rickettsia rickettsii A species of gram-negative, aerobic bacteria that is the etiologic agent of ROCKY MOUNTAIN SPOTTED FEVER. Its cells are slightly smaller and more uniform in size than those of RICKETTSIA PROWAZEKII.
Synonyms :
Rickettsia typhi The etiologic agent of murine typhus (see TYPHUS, ENDEMIC FLEA-BORNE).
Synonyms :
Rickettsiaceae A family of small, gram-negative organisms, often parasitic in humans and other animals, causing diseases that may be transmitted by invertebrate vectors.