Leptospirosis is a disease caused by spiral shaped bacteria called leptospires. It occurs worldwide and can affect humans as well as many wild and domestic animals, including dogs and cats. The disease can be serious for both humans and animals.
How are dogs infected?
The bacteria, spread through the urine of infected animals, gets into water or soil and can survive there for weeks to months. Humans and animals can become infected through contact with this contaminated urine (or other body fluids, except saliva), water, or soil. The bacteria can enter the body through skin or mucous membranes (eyes, nose, or mouth), especially if the skin is broken from a cut or scratch. Drinking contaminated water can also cause infection. Infected wild and domestic animals may continue to excrete the bacteria into the environment continuously or every once in a while for anywhere from a few months to up to several years.
What are the signs of leptospirosis?
In people, the symptoms are often like the flu, but sometimes leptospirosis can develop into a more severe, life-threatening illness with infections in the kidney, liver, brain, lung, and heart. For more information on leptospirosis in humans, look at the flowing site:
In animals, the clinical signs of leptospirosis vary and are nonspecific. Sometimes pets do not have any symptoms. Common clinical signs reported in dogs include fever, vomiting, abdominal pain, diarrhea, refusal to eat, severe weakness and depression, stiffness, severe muscle pain, or inability to have puppies. Generally, younger animals are more seriously affected than older animals.
There are three main forms of the disease:
- Hemorrhagic (bleeding)
- Icteric or jaundice (liver)
- Renal (kidney)
In hemorrhagic disease there is a high fever with lethargy and loss of appetite. Multiple small hemorrhages occur in the mouth and on the whites of the eyes. Bloody diarrhea and vomiting may occur. This form is often fatal.
The icteric, or jaundice, form begins much like the hemorrhagic form, and many of the clinical signs are the same. It differs in the presence of a yellow color, called jaundice or icterus, in the mouth and whites of the eyes. In severe cases the skin will turn yellow.
The renal form causes kidney failure. These dogs are very lethargic, have little or no appetite, and may vomit. Their breath may have a very offensive odor, and ulcers often develop on the tongue. Other signs include diarrhea, excessive drinking, and excessively frequent urination. There may be red staining of the urine (blood). The dog may be reluctant to move and may show abdominal discomfort. Fever is variable, and temperature may actually be below normal in the more advanced stage. Dogs that survive the acute renal form may be left with chronic kidney disease.
How is leptospirosis diagnosed?
Because the clinical signs are variable and easily confused with other diseases, diagnosis can be difficult. There are no readily available rapid and definitive laboratory tests. A diagnosis is supported by taking blood samples during infection and again in the recovery period and showing an increase in antibodies to Leptospira in the blood serum (at least a four-fold increase in antibody titer). A single test finding of Leptospira antibody, even if the blood level (titer) is high, may not mean that the dog has Leptospirosis because infection with less harmful serovars can still result in high antibody levels.
What is the treatment?
Antibiotics are reasonably effective if begun early. Most affected dogs require intensive care in the veterinary hospital. An extended course of antibiotics may be prescribed even in the recovery period to ensure that all of the Leptospira organisms are cleared, and the dog does not become a chronic carrier.
How can leptospirosis be prevented?
The vaccine for leptospirosis is not always a part of the routine vaccination program for all dogs. Your veterinarian will consider the risks and options for your pet. Annual boosters may be needed to maintain best immunity.
Can the vaccine cause side-effects?
Of the components of a dog’s vaccination program, the portion for leptospirosis has been reported to be one of the more likely to cause a reaction. This usually takes the form of lethargy for a few days and possibly loss of appetite. In some dogs (Miniature Dachshunds and West Highland White Terriers seem to have slightly increased risk) a more general shock-like reaction may occur shortly after vaccination. Other dogs may develop a skin rash (urticaria), apparent on hairless areas. These reactions can be controlled medically, so if you are concerned call your veterinarian immediately.