In dogs: Symptoms are variable and are most commonly associated with kidney damage which may include fever, lethargy, low appetite, vomiting and increased or decreased urination and thirst. Diarrhea and liver damage or yellowed mucus membranes (gums) may also be seen.

In humans: Symptoms are variable and may include fever, severe headache, and muscle aches. In severe cases, people may have yellowed mucus membranes, cause kidney damage and respiratory distress. Click here to learn more about lepto in people.