UMEM Educational Pearls

Title: Relapsing Fever

Category: International EM

Keywords: international, fever, Borrelia, tick, louse (PubMed Search)

Posted: 10/24/2012 by Andrea Tenner, MD (Updated: 11/22/2024)
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Causative organism: members of the genus Borrelia
- Louse Borne Relapsing Fever (LBRF)
  - Human body louse (Pediculus humanus)
  - Associated with sporadic outbreaks especially in areas with large refugee populations
- Tick Borne Relapsing Fever (TBRF)
  - Soft ticks of the genus Ornithodoros
  - Typically found in higher elevations of the western United States as well as the central plateau region of Mexico, Central and South America and Africa
Clinical Presentation
- Symptoms develop 3 to 18 days after infection.
- Onset is abrupt and may include fever, malaise, headache, arthralgias, nausea and vomiting and cough.
- The first febrile episode lasts 3 to 6 days and then recurrences may occur after 7 to 10 days.
Diagnosis
- Definitive diagnosis: visualization of spirochetes on peripheral blood smear.
- May also see leukocytosis, anemia and/or thrombocytopenia, elevation of liver function tests
- Erythrocyte rosette formation may be present.
Treatment
- Antibiotics recommended for treatment include penicillin, doxycycline and erythromycin.
- Jarisch-Herxheimer reaction common after treatment. This can be life threatening and all patients undergoing treatment should be closely monitored.

University of Maryland Section for Global Emergency Health

Author: Gentry Wilkerson

Centers for Disease Control and Prevention CDC. Tickborne relapsing fever in a mother and newborn child--Colorado, 2011. MMWR Morb Mortal Wkly Rep. 2012;61(10):174–176.
Larsson C, Andersson M, Bergström S. Current issues in relapsing fever. Curr Opin Infect Dis. 2009;22(5):443–449.