Leptospirosis is a bacterial infection often caused by contaminated water. Dogs who drink or swim
in tainted water can become infected, but the bacteria can also penetrate a dog’s skin. Lepto is carried by wild animals such as deer, skunk, rats and raccoons, who spread the bacteria through their urine. Domesticated livestock also carry the bacteria. Leptospirosis can be transmitted to humans, making it a serious concern for owners of outdoor dogs. Dogs can also contract the infection through bites and by eating contaminated materials.
There are about 230 strains of leptospira bacteria, four of which are the most common causes of canine infections. In the U.S., the disease is most prevalent in tropical climates, in states with heavy rainfall, but occurs in many other areas as well. Dry, cold conditions can kill the bacteria, but they can persist in mud, standing water, damp areas and alkaline conditions.
Your veterinarian can detect lepto infection, which sometimes causes no symptoms but can also result in life-threatening illnesses. Normally, the bacteria trigger antibodies that may clear the infection, but sometimes this mechanism fails. The three main forms of leptospirosis infection disease are:
Kidney disease: This is the primary form of the infection, and can result in kidney failure. Symptoms include lethargy, appetite loss, diarrhea, drooling and vomiting. The dog might suffer from bad breath, tongue sores and abdominal pain. Chronic kidney infection can be fatal.
Bleeding: Hemorrhagic disease is frequently fatal. Dogs can exhibit lethargy, high fever, loss of appetite and bleeding from the mouth and eyes. The bacteria can suppress blood’s ability to clot.
Liver disease: This form has similar symptoms to hemorrhagic disease and hepatitis, but also include jaundice (yellowing for the skin, eyes and mouth).
Veterinarians must contend with the fact that these symptoms indicate various diseases, and the signs of infection can be ambiguous. To nail down the diagnosis, your vet will order blood and urine tests, looking for elevated white-blood-cell counts, as well as abnormalities in liver enzymes, blood-clotting cells and kidney health values. Definitive identification is achieved by the leptospirosis polymerase chain reaction (PCR) test, which amplifies certain portions of the bacteria’s DNA. In some cases, living leptospiral can be detected in the dog’s urine.
The most vulnerable dogs are younger than six months and/or have not received a vaccination against infection. A gestation period of 4 to 12 days precedes the appearance of symptoms. The infection spreads rapidly throughout the bloodstream, creating powerful toxins that attack internal organs. In later stages, an infected dog might pass blood in its urine and suffer low body temperature.
You can avoid cross-infection by observing hygienic behavior, especially when coming into contact with your dog’s urine. The danger of cross infection can persist for months after your dog is cured as it continues to shed lepto bacteria. If you have an infected dog, isolate it from other pets in an easily sanitized area. Frequently walk your dog to allow it to urinate, preferably on a dry concrete surface that can be disinfected with bleach. If your skin comes into contact with potentially infected material, wash the area with iodine-based disinfectant. If you feel ill, contact your physician.
In terms of prevention and treatment, your vet can administer a vaccination, to protect your dog from leptospirosis. Protection lasts about a year, so re-vaccination is necessary. You can help prevent the disease by making sure your pet isn’t exposed to contaminated water, and do not allow your dog to eat wild critters. It might counter your generous instincts, but it’s probably not a good idea to put out food for feral cats and other wild animals.
An infected dog can be treated with antibiotics, including doxycycline, tetracycline, penicillin and erythromycin. Symptomatic relief can include anti-emetics (to reduce vomiting) and perhaps intravenous fluids to correct the dog’s acid/base balance, flush the kidneys and prevent dehydration. When the kidneys have been damaged, dialysis might be useful. Dogs that come down with chronic hepatitis or renal failure might not survive. Dogs cured of leptospirosis can be reinfected unless they receive regular vaccinations. Your veterinarian can answer all your questions about leptospirosis.
Dr. Paul has a strong interest in avian and exotic animal medicine and surgery, as well as small animal internal medicine and surgery.
He has provided services for numerous breeders, kennels, aviaries, and mini zoos.