Leptospirosis, a disease affecting humans and animals

Leptospirosis is a bacterial disease that affects humans and animals. It is caused by bacteria of the genus Leptospira. In people, it can cause a wide range of symptoms, some of which may be mistaken for other diseases, while some may have no symptoms at all.


Without treatment, Leptospirosis can lead to kidney damage, meningitis (inflammation of the membrane around the brain and spinal cord), liver failure, respiratory distress, and even death.


The infection rate for domestic pets has been increasing, occurring most commonly in the fall. Dogs will typically come into contact with the leptospira bacteria in infected water, soil, or mud, while swimming, passing through, or drinking contaminated water, or from coming into contact with urine from an infected animal.  That can even mean just walking on the lawn.

The species of infected reservoir animals varies in each region of the country. In some areas it is raccoons, deer, skunks, foxes, coyotes, farm animals in some, rats and mice.  Even urban areas can have mice and rats so we do see cases of lepto in urban dogs.


Symptoms of leptospirosis infection include:

•Sudden fever and illness



•Lack of appetite

•Increased thirst and urination, due to kidney failure




•Yellow skin and/or whites of eyes


Leptospirosis is diagnosed through a blood test.  Treatment includes hospitalization for supportive care, and medication.  Some dogs exposed to lepto recover without treatment because they never show symptoms.  An untreated dog who recovers from the infection can become a carrier and shed the bacteria in urine for up to a year. Unfortunately lepto can be zoonotic, meaning people are at risk of acquiring the infection.  Proper sanitation must be practiced when handling infected animals and the urine.

If your dog is at risk for contracting lepto, there is a vaccination that can be added to your pets annual vaccine protocol.