Epidemiology

Most commonly found in tropical climates

Etiology

Pathogen: Leptospira (especially L. interrogans sensu lato), a genus of gram-negative spirochete with hook-shaped ends
- Spirochetes cannot be visualized using Gram staining and require specialized staining methods.
Transmission
- Sources
  - Urine, blood, or tissue of an infected animal (most commonly rats)
  - Environmental contamination (e.g., water contaminated with urine of infected animals)
- Entry points: broken skin or exposed mucous membranes (e.g., conjunctiva, oral mucosa)
- Risk factors
  - Occupations that involve direct or indirect contact with animals (e.g., agricultural or sewage workers)
  - Freshwater recreational activities (e.g., canoeing, swimming, windsurfing)