Rocky Mountain spotted fever

Last Updated: 2019-08-27

Author(s): Anzengruber F., Navarini A.

ICD11: -

American rock fever, New World tick bite fever.

Rickettsia rickettsii occurring by Rickettsia rickettsii.

  • Spread all over the world.
  • Especially in the American continent (especially during the spring or summer months).
  • Children between the ages of 4 and 10 are mostly affected.

  • Pathogen: Rickettsia rickettsii, Rickettsia rickettsii is transmitted by tick bites.

  • Incubation period: 2-14 days.
  • In the area of the inoculation site a partly ulcerated, possibly encrusted papule appears.
  • Maculopapular exanthema (initial at wrists and ankles).
  • Nosebleeds, fever, splenohepatomegaly.
  • Kidney, liver and CNS may become involved.

  • Travel medical history
  • Clinic.
  • Lice infestation.
  • Blood count, liver and kidney values, electrolytes.
  • From the 2nd week of illness Weil-Felix reaction (agglutination test).
  • From the 3rd week of the disease, complement fixation reaction. 
  • Indirect immunofluorescence test from the 3rd week of the disease.

Letality: 5-25%.

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  2. Elghetany, M.T. and D.H. Walker, Hemostatic Changes in Rocky Mountain Spotted Fever and Mediterranean Spotted Fever. American Journal of Clinical Pathology, 1999. 112(2): p. 159-168.
  3. Helmick, C.G., K.W. Bernard, and L.J. D'Angelo, Rocky Mountain Spotted Fever: Clinical, Laboratory, and Epidemiological Features of 262 Cases. Journal of Infectious Diseases, 1984. 150(4): p. 480-488.
  4. Holman, Robert C., et al., Analysis of Risk Factors for Fatal Rocky Mountain Spotted Fever: Evidence for Superiority of Tetracyclines for Therapy. The Journal of Infectious Diseases, 2001. 184(11): p. 1437-1444.
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  7. Ricketts, H.T., A Micro-Organism which Apparently Has a Specific Relationship to Rocky Mountain Spotted Fever. JAMA, 1909. LII(6): p. 491.
  8. Spolidorio, M.G., et al., Novel spotted fever group rickettsiosis, Brazil. Emerg Infect Dis, 2010. 16(3): p. 521-3.
  9. Thorner, A.R., D.H. Walker, and J.W.A. Petri, Rocky Mountain Spotted Fever. Clinical Infectious Diseases, 1998. 27(6): p. 1353-1359.
  10. Walker, D.H., Rickettsia rickettsii and Other Spotted Fever Group Rickettsiae (Rocky Mountain Spotted Fever and Other Spotted Fevers), in Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases. 2010, Elsevier BV. p. 2499-2507.