Symptoms and Signs of Leptospirosis in Dogs

Source: PetWave, Updated on July 16, 2015
Leptospirosis

Effects of Leptospirosis

Leptospirosis is a bacterial infection that tends to target the kidneys and liver of domestic dogs and, less commonly, cats. Most dogs infected with Leptospira never actually become sick. However, they still carry the bacteria inside their bodies and shed it in their urine and other bodily secretions, which makes them a source of infection for other animals. Dogs that do develop clinical signs of leptospirosis will be sore, stiff and somewhat depressed. They may be reluctant to move. They also may lose their appetite, and lose weight. Basically, they will just feel lousy, and won’t have their normal “get-up-and-go.”

Symptoms of Leptospirosis

Owners of dogs with leptospirosis usually won’t see any signs of sickness. However, occasionally they will have a very ill dog. The observable signs of this infection are highly variable. In rare cases, infected dogs die suddenly, without showing any prior symptoms of illness. Fortunately, this is extremely uncommon. In most cases, dogs infected with Leptospira don’t actually become “sick.” When they do become sick, their owners may notice one or more of the following clinical signs:

  • Fever
  • Lethargy
  • Weakness
  • Depression
  • Loss of appetite (inappetence; anorexia)
  • Shivering; shaking (tremors)
  • Vomiting (emesis; may contain blood)
  • Nose bleeds (epistaxis)
  • Muscle tenderness; soreness; stiffness
  • Reluctance to rise or move
  • Exercise intolerance
  • Cough
  • Difficulty breathing (respiratory distress; dyspnea)
  • Elevated respiratory rate (tachypnea)
  • Back pain
  • Increased frequency of urination (pollakiuria)
  • Increased volume of urine output (polyuria)
  • Increased thirst/water intake (polydipsia)
  • Bloody vaginal discharge
  • Blood in the urine (hematuria)
  • Dehydration
  • Diarrhea (with or without blood)
  • Injected (very red) mucous membranes

Dogs at Increased Risk

Middle-aged male dogs tend to become clinically affected by leptospirosis more commonly than other dogs. Large-breed dogs also develop signs of this disease more often than smaller dogs. The association between leptospirosis and large male dogs may be more related to the free-roaming activities of those animals than to their genetic make-up. Leptospirosis is most prevalent in rural areas, where the bacteria are harbored by wildlife. However, pets in urban areas are increasingly at risk due to mutations of the Leptospira bacteria and the preponderance of rats that carry these organisms. Dogs with access to stagnant water or raw sewage, and those that come into contact with rats, raccoons or opossums, have an increased chance of developing leptospirosis. Dogs used for hunting, and those that otherwise frequent wet wooded areas, are at increased risk as well.

Special Notes

Leptospirosis used to be considered a fairly uncommon disease in domestic dogs. It was primarily diagnosed in remote rural areas frequented by wildlife. However, the various strains (serovars) of Leptospira have mutated over time, and the disease is on the rise among pet dogs that live in urban areas because of the proliferation of rats that are attracted to trash and other dirty environments. People can become infected by Leptospira by the same routes that their pets can become infected. Usually, this is by direct contact with urine or other bodily fluids from an infected animal.

Dog Health Center

Lead Poisoning

Dogs can be poisoned when they ingest lead – especially if they have repeated exposure to the substance. Lead is found in a number of places and in a number of different things

Learn more about: Lead Poisoning