What is Weil's disease caused by?

Weil's disease is caused by the bacterium Leptospira interrogans. This organism belongs to the genus Leptospira, which is a group of spirochete bacteria. These bacteria are primarily found in the urine of infected animals, particularly rodents, and can be transmitted to humans through direct contact with contaminated water, soil, or through breaks in the skin.

Infection with Leptospira interrogans can lead to a range of symptoms, including high fever, chills, muscle aches, and in severe cases, jaundice, renal failure, and hemorrhaging. The disease is part of a broader group known as leptospirosis, which can vary in severity based on the strain of the bacteria and the immune response of the individual.

The other options provided do not cause Weil's disease, as each relates to a distinct pathogen and associated illnesses. Escherichia coli is commonly linked to gastrointestinal infections, Salmonella typhi is the causative agent of typhoid fever, and Vibrio cholerae is responsible for cholera. Each of these has its own modes of transmission and clinical manifestations, which differ significantly from those of Weil's disease.