Last reviewed: November 2017
Last updated: October  2016



History and exam

Key diagnostic factors

  • eschar
  • lymphadenopathy associated with eschar

Other diagnostic factors

  • fever >38°C
  • rash
  • thrombocytopenia
  • abnormal liver function tests
  • hyponatraemia
  • travel to tropics
  • lymphopenia

Risk factors

  • exposure to human body lice
  • exposure to rodents (rats and mice) and their fleas
  • tick bites
  • mite bites (Southeast Asia, Oceania, northern Australia)
  • returned traveller from the tropics
  • exposure to natural vegetation, forests, scrub, bush
  • exposure to cat or dog fleas

Diagnostic investigations

1st investigations to order

  • FBC
  • serum electrolytes
  • C-reactive protein
  • rickettsial serology
  • rickettsial molecular tests
Full details

Investigations to consider

  • chest x-ray
  • trial of doxycycline therapy
Full details

Treatment algorithm


Authors VIEW ALL

Founder and Medical Director

Australian Rickettsial Reference Laboratory




SRG is the founder of a not-for-profit diagnostic and research microbiology laboratory that undertakes diagnostic testing on referred patient specimens. Income from this testing, mainly from the Australian government, is used to support the research activities of the laboratory. SRG is the author of a reference cited in this monograph.

Peer reviewers VIEW ALL


Department of Medicine

University of Peradeniya


Sri Lanka


SAMK declares that he has no competing interests.

Professor of Medicine and Pathology

Albert Einstein College of Medicine

New York City



LW's laboratory research programme is supported by NIH (NIAID) grants. He performs infectious diseases consultation at Montefiore (Weiler Hospital).

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