Leptospirosis is an infectious disease caused by spirochaetes, a type of bacteria from the genus Leptospira. Dogs suffering from Leptospirosis can develop vasculitis, liver and kidney failure. Leptospirosis is not limited to dogs; it can infect a wide range of animals, including mammals, birds, and reptiles. It can also infect humans. Leptospirosis is known under many different names, including Canicola fever, 7-day fever, Weil’s disease, Canefield fever, and Nanukayami.

Leptospirosis transmission

Leptospirosis is transmitted via the urine of infected animals and a dog can get Leptospirosis by licking urine from grass or other surfaces or by drinking water from a puddle contaminated with urine. The urine has to be moist, because the spirochaetes die if dried out. It is theoretically possible to get Leptospirosis when playing in water, but it is very unlikely since the spirochaetes don’t live naturally in freshwater. The spirochetes causing Leptospirosis can only survive a few days outside a host animal. The infectious cycle normally of consist of infected animals, such as rats, rabbits, raccoons and cows, that carries the spirochaetes to a ditch, muddy riverbank, gulley or similar. New animals become infected from the moist mud, and the cycle continues. Leptospirosis is less common during periods of little or no rainfall.
Leptospirosis can also be transmitted via blood and semen.

Leptospirosis symptoms in dogs

In dogs, the incubation period normally varies from 2 to 20 days. The spirochaetes attacks the liver and kidneys of the dog and can cause vasculitis, which in turn leads to oedema. Vomiting, loss of appetite or failure to eat, reduced urine output, abnormally dark or brown urine, fever, and lethargy are all symptoms of Leptospirosis in dogs. The condition can develop into disseminated intravascular coagulation (DIC). Other health problems associated with Leptospirosis in dogs are meningitis, uveitis, pericarditis, and myocarditis. It is very common for infected dogs to display a yellowing of the eyes, but some dogs never get jaundiced eyes. (Keep in mind that yellowing eyes can be caused by other diseases as well, such as hepatitis.) 

Leptospirosis vaccine for dogs

There is no vaccine approved for use on humans, but animal vaccines exist for a few strains of bacteria from the genus Leptospira. Unfortunately, the vaccine will only work for a few months and it is therefore not very commonly used on dogs. 

Leptospirosis treatment for dogs

Leptospirosis treatment for dogs must consist of two parts: one part that suppresses the spirochetes and one part that fights possible complications. One of the most commonly used methods when treating dogs with Leptospirosis is to use penicillin to end the leptospiremic phase (where the spirochetes are found in the blood) and doxycycline to end the carrier state.

In severe cases of Leptospirosis, detoxication and normalization of the hydro-electrolytic balance can be necessary since the spirochetes attacks important inner organs in the dog. The vet can administer solutions containing salt and glucose, and dialysis is also an option. 

If you suspect that you dog might be infected with Leptospirosis, it is important to seek veterinary attention. Fast and proper treatment will greatly increase the survival rate for dogs suffering from Leptospirosis. It is also important to prevent further transmission of the disease. 

Bacterial infections in dogs: (click for more info)
Aspergillosis in dogs
Brucellosis in dogs
Clostridium in dogs
Ehrlichiosis in dogs
Leptospirosis in dogs
Rocky Mountain spotted fever in dogs