Leptospirosis occurs in many wild and domestic animals. People acquire these infections through contact with the animal or its urine. Although leptospirosis is an occupational disease of farmers and sewer and slaughterhouse workers, most people become infected during such activities as swimming in, walking through or otherwise coming into contact with contaminated water.
Infection can enter through a cut in the foot or other part of the body.
In Indonesia, there was recently an outbreak in Kalimantan from drinking soft drinks. It is thought the urine of rats soaked through the cardboard box onto the soft drinks and then into the mouth of people who did not wipe the top of their cans. Because leptospirosis typically causes vague flulike symptoms, many cases probably go unreported. Periods of flooding also increase the incidence of leptospirosis. Read what happened to participants in the Eco-Challenge Sabah 2000 Expedition Race .