SpecialtyInfectious disease

A rickettsiosis is a disease caused by intracellular bacteria.


Rickettsioses can be divided into a spotted fever group (SPG) and typhus group (TG).[1]

In the past, rickettsioses were considered to be caused by species of Rickettsia.[2] However, scrub typhus is still considered a rickettsiosis, even though the causative organism has been reclassified from Rickettsia tsutsugamushi to Orientia tsutsugamushi.

Examples of rickettsioses include typhus, both endemic and epidemic, Rocky Mountain spotted fever, and Rickettsialpox.

Organisms involved include Rickettsia parkeri.[3]

Many new causative organisms have been identified in the last few decades.[4]

Most are in the genus Rickettsia, but scrub typhus is in the genus Orientia.[5]


No rapid laboratory tests are available to diagnose rickettsial diseases early in the course of illness, and serologic assays usually take 10–12 days to become positive. Research is indicating that swabs of eschars may be used for molecular detection of rickettsial infections.[6][7]


Doxycycline has been used in the treatment of rickettsial infection.[8]


  1. ^ Choi YJ, Jang WJ, Ryu JS, et al. (February 2005). "Spotted fever group and typhus group rickettsioses in humans, South Korea". Emerging Infect. Dis. 11 (2): 237–44. doi:10.3201/eid1102.040603. PMC 3320442. PMID 15752441.
  2. ^ Raoult D, Roux V (October 1997). "Rickettsioses as paradigms of new or emerging infectious diseases". Clin. Microbiol. Rev. 10 (4): 694–719. doi:10.1128/CMR.10.4.694. PMC 172941. PMID 9336669.
  3. ^ Paddock CD, Finley RW, Wright CS, et al. (November 2008). "Rickettsia parkeri rickettsiosis and its clinical distinction from Rocky Mountain spotted fever". Clin. Infect. Dis. 47 (9): 1188–96. doi:10.1086/592254. PMID 18808353.
  4. ^ Parola P, Paddock CD, Raoult D (October 2005). "Tick-Borne Rickettsioses around the World: Emerging Diseases Challenging Old Concepts". Clin. Microbiol. Rev. 18 (4): 719–56. doi:10.1128/CMR.18.4.719-756.2005. PMC 1265907. PMID 16223955.
  5. ^ Unsworth NB, Stenos J, Faa AG, Graves SR (July 2007). "Three Rickettsioses, Darnley Island, Australia". Emerging Infect. Dis. 13 (7): 1105–7. doi:10.3201/eid1307.050088. PMC 2878210. PMID 18214193.
  6. ^ Angelakis, Emmanouil; Richet, Hervé; Rolain, Jean-Marc; La Scola, Bernard; Raoult, Didier (2012). "Comparison of real-time quantitative PCR and culture for the diagnosis of emerging Rickettsioses". PLoS Neglected Tropical Diseases. 6 (3): e1540. doi:10.1371/journal.pntd.0001540. ISSN 1935-2735. PMC 3295807. PMID 22413026.
  7. ^ Giulieri, Stefano; Jaton, Katia; Cometta, Alain; Trellu, Laurence T.; Greub, Gilbert (February 2012). "Development of a duplex real-time PCR for the detection of Rickettsia spp. and typhus group rickettsia in clinical samples" (PDF). FEMS Immunology and Medical Microbiology. 64 (1): 92–97. doi:10.1111/j.1574-695X.2011.00910.x. ISSN 1574-695X. PMID 22098502.
  8. ^ "eMedicine - Rickettsial Infection : Article by Mobeen H Rathore".
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