What is Leptospirosis (Weil's Disease)?

Leptospirosis is a bacterial infection spread through contact with water or soil contaminated with the urine of infected animals, particularly rats, most commonly affecting people who swim, kayak, or work in fresh water or damp environments. Most cases cause flu-like symptoms — fever, headache, muscle aches — and resolve without serious complications.

A small proportion of cases progress to a more severe form (sometimes called Weil's disease), which can affect the liver, kidneys, and other organs, and needs prompt hospital treatment. Early antibiotic treatment for suspected leptospirosis reduces the risk of this more severe illness.