Leptospirosis is a bacterial infection. It is transmitted in animal urine; exposure to rat urine has been blamed for some cases. High fever, severe headache, chills, muscle aches, vomiting, diarrhea, and jaundice (yellow skin and eyes) may occur. This may lead to kidney damage, meningitis (inflammation of the membrane around the brain and spinal cord), liver failure, and respiratory distress. Death is rare.
For more information, see the Centers for Disease Control (CDC).