Leptospirosis is a bacterial infection that is usually spread through water, food, or soil contaminated by the urine of infected animals. Dogs and rats are the most common domestic animals that spread the infection to people.

Symptoms of leptospirosis, if they develop, often begin suddenly and may include severe headache, sensitivity to light, sweating, chills, muscle aches, stomach pain, vomiting, diarrhea, red eyes, rash, and a high fever.

If the disease is not treated, recovery may take several months, and serious health problems may result, such as kidney damage or liver failure. In rare cases, death may occur.

Leptospirosis is diagnosed with laboratory tests of blood or urine samples and is treated with antibiotics.