Leptospirosis is an infectious bacterial disease that affects both humans and animals. Humans become infected through direct contact with the urine of infected animals or through urine-contaminated environments, where the bacteria enter into the system through cuts and abrasions of the skin or through the eyes, nose, and mouth. Leptospirosis occurs worldwide, but is most prevalent in tropical and subtropical regions, with outbreaks common following excessive rainfall or flooding. Signs and symptoms of leptospirosis can range from a mild flu-like illness to a more serious and sometimes fatal disease. In the early stages, symptoms include high fever, severe headache, muscle pain, chills, redness of the eyes, hives, abdominal pain, jaundice, hemorrhages in the skin, vomiting, diarrhea, and rash.