Typhus fever

**Definition:** A disease caused by an infection with the gram-negative bacteria Rickettsia. This disease is characterised by fever, delirium, back pain, or arthralgia. Transmission is commonly through the bite of an infected flea, louse, mite, or tick.

**Long definition:** Group of acute, arthropod borne infections caused by rickettsiae; includes epidemic (classic or louse-borne) typhus, its recrudescent form, and murine (endemic or flea-borne) typhus; all are characterized by severe headache, chills, high fever, stupor, and rash.

**Exclusions:** - Rickettsiosis due to Ehrlichia sennetsu