Leptospirosis: My dog is vaccinated for it, but what is it?

Written by Erik Melin, DVM.


Leptospirosis is a corkscrew shaped bacteria that can be infectious to your dog. It carries extra significance because if your dog becomes infected, it could give it to you.

 

How can my dog become infected?

Wild animals, or infected domestic animals, are the source of Leptospirosis and maintain its existence in nature. There are two ways a dog can become infected. A dog can become directly infected if it is exposed to an infected animals urine or venereal secretions, or if it is bitten or ingests infected tissue. Indirect infection occurs if the dog is exposed to contaminated water, food, bedding or soil. The most common way a dog becomes infected is through a wound or prolonged exposure to the skin.

What happens if my dog becomes infected?

Once the bacteria enters the body, it spreads through the bloodstream to the kidneys, liver, spleen, eyes, central nervous system and urogenital tract. The kidneys are especially susceptible, and one of the most common problems seen with Leptospirosis is kidney failure. Fortunately, the damage to the kidneys is usually temporary once treatment is started. Likewise the liver is also commonly affected.

 

What are the signs of Leptospirosis?

Infected dogs often show signs of liver disease (jaundice or yellow tone to skin), kidney disease (increased drinking and urination), or more general signs of illness such as depression, lethargy, loss of appetite, weight loss, fever and muscle pain. In rare cases with central nervous system involvement, loss of balance or seizures may be seen.

 

How is Leptospirosis diagnosed?

Because the signs of Leptospirosis are not specific to that disease a physical exam is followed by running a complete blood count (CBC), serum chemistry profile and urinalysis. Typical abnormalities on the CBC include an elevated white blood cell count and low platelet count. Depending on what organs may be involved the serum chemistry profile may show elevated kidney values, elevated liver enzymes and electrolyte abnormalities. If leptospirosis is suspected, a specific blood test can be done to verify the diagnosis and ensure the correct therapy is instituted.

 

How is Leptospirosis treated?

Leptospirosis is treated with a combination of antibiotics and supportive care. Antibiotics are often given for four weeks or longer. The amount of supportive care the patient needs depends on the current condition of the dog. Intravenous or subcutaneous fluids, medications to prevent or relieve gastrointestinal irritation and specific foods are often prescribed. In the more severe, life-threatening, cases more aggressive therapy may be required.

 

How can Leptospirosis be prevented?

There are eight strains of leptospirosis that cause illness in domestic dogs. Until recently only two have been available as a vaccine. Through the use of that vaccine the prevalence of those two strains has decreased significantly. Recently a vaccine containing four strains of the bacteria was developed and we believe using this 4-way vaccine is the best way to prevent infection with leptospirosis.

Dogs that spend the most time outdoors are the most susceptible to contracting leptospirosis. However, the wild animals that carry the bacteria are prevalent even in metropolitan areas, making all animals susceptible.