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INFORMATION:  Leptospirosis is a bacterial disease of dogs and other mammals that primarily affects the liver and or kidneys.  There are many species and serovars of Leptospirosis.  Leptospirosis bacteria are carried mainly by rodents, raccoons, deer, and cattle but can also affect almost any mammalian species, including people.  Dogs that have been previously infected or recovered “carrier” dogs many act as a source of the infection.  Ingestion of infected urine or rodent contaminated garbage is the most important means of transmission, but some forms of the bacteria can penetrate damaged or thin skin.  For example, when dogs swim in contaminated water (contaminated by livestock urine) they may become infected through their skin.  The incubation period is four to twelve days.



PREVENTION: The vaccine for leptospirosis is not always part of the routine vaccination program for dogs.  It is the “L” in the DHLPP vaccine.  Our recommendation is that all dogs that are around livestock, wildlife, ponds or lakes and other stagnant water sources, weigh more than 25 pounds or that spend lots of time outdoors should be routinely vaccinated for this disease.  Annual boosters are needed to maintain the best immunity.  If your dog has never had a leptospirosis vaccination before he/she will need a series of two vaccinations 1 month apart to provide immunity. 

      Small dogs have a higher likelihood of vaccine reactions to leptospirosis and generally spend more time indoors so have much less risk of developing the disease so we do not routinely vaccinate them for leptospirosis. Dachshunds and other toy breeds seem to have a greater risk for vaccine reactions to the leptospirosis vaccine.



ZOONOSIS: When deciding if you should vaccinate your dog for leptospirosis, remember that the disease is zoonotic which means the disease can be transmitted to humans.  Humans can develop the disease from contaminated urine from dogs or other mammals or from swimming in a stagnate body of water.



SYMPTOMS: Many cases of leptospirosis go undetected, but other cases can be life-threatening.  Certain strains of leptospirosis are more likely to be associated with disease than other strains and the icterohemorrhagiae serovar is the most dangerous.  There are three main forms of the disease:  Hemorrhagic, Icteric or Renal, but often cases will have both the icteric and renal form.

      Hemorrhagic form:  This form is often fatal and starts with a high fever, lethargy, anorexia.  Multiple small hemorrhages or petechia occur in the mouth and on the whites of the eyes, and dogs can develop massive pulmonary hemorrhage.  Bloody diarrhea and vomiting may occur.

      Icteric or jaundice form: This form begins like the hemorrhagic form but it differs in the presence of a yellow color (jaundice or icterus) in the mouth and the whites of the eyes.  In severe cases the skin will turn yellow.  This is the form that involves the liver primarily.

      Renal form:  causes kidney failure.  These dogs are very lethargic, anorectic, and may vomit.  Their breath may have a very offensive odor and ulcers develop on the tongue.  Other signs include diarrhea, excessive drinking, and excessive urination.  There may be red staining of the urine (blood).  The dog may be reluctant to move and show abdominal discomfort.  Dogs that survive the acute renal form may be left with chronic kidney disease. 


Leptospirosis can be difficult to diagnose because the signs are variable and can be confused with other diseases.  There are no readily available rapid and definitive laboratory tests.  Rising serum antibody titers can be useful in determining if your dog has leptospirosis.  Treatment for leptospirosis is antibiotics and intensive supportive care in a veterinary hospital and can be successful if started early enough.



What it is and how to protect yourself and your dog from the bacteria. 

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