Microscopy: Thick and thin blood films or dark-field microscopy → spirochetes visible during febrile episodes.
Serology/PCR: confirmation (if available).
💊 Management
First-line: Doxycycline 100 mg PO BD for 7–10 days.
Alternative: Procaine penicillin (IM) or Tetracycline if doxycycline unsuitable.
Jarisch–Herxheimer reaction: common (acute fever, rigors, hypotension within hours of treatment) → supportive management with fluids, antipyretics, and close monitoring.
Supportive care: fluids, oxygen, monitoring for bleeding and neurological complications.
⚠️ Public Health
Louse control (improved hygiene, insecticides) is critical for prevention.
Relapsing fever is associated with refugee camps, war zones, and areas of poor sanitation.