When Do Dogs Start Showing Signs of Leptospirosis?

Leptospirosis bacteria thrive in warm weather and moist conditions.
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In most parts of the United States, the bacteria Leptospira interrogans thrive in soil and water. The bacteria cause the infection called leptospirosis. It's easily transmitted and quite common in canines, but not all infected dogs become ill. Some might spike a brief fever and then go back to normal. For certain dogs, though, the infection becomes deadly. Dogs generally show symptoms of leptospirosis infection within two days to a month after exposure.

Leptospirosis in Dogs

In dogs exposed to leptospirosis, the spirochetes -- forms of twisted bacteria -- spread throughout the dogs' bodies, reproducing as they go. They dwell in the reproductive and central nervous systems, as well as the eyes, liver and kidneys. Many dogs mount an immune response within eight to 10 days after exposure, producing antibodies that fight the infection. Even if these dogs remain asymptomatic, they can still spread the infection through urine. Leptospirosis isn't limited to dogs. It's a zoonotic disease that affects many warm-blooded animals -- and people. An annual vaccination can protect your pet. It's especially wise to vaccinate hunting and sporting dogs who spend a lot of time in water.

Leptospirosis Exposure

Dogs generally acquire leptospirosis after coming into contact with an infected animal's urine. That's because the bacteria are shed every time an infected animal pees, contaminating anything his urine splashes on. Other avenues for infection include sexual contact, consumptionof infected animals, bite wounds or other open lesions, and just physically touching other infected dogs. The bacteria can enter the dog's system via the lining of the eyes, nose and mouth. Pregnant dogs can transmit the bacteria to their unborn puppies. If you believe your dog has been exposed to leptospirosis but shows no signs of illness, take him to your veterinarian. She can prescribe antibiotics that can prevent the disease.

Leptospirosis Symptoms

Dogs with healthy immune systems can often fight off the infection; old dogs, puppies and animals with compromised immune systems are at higher risk. Infection symptoms include fever, shivering, lack of appetite, lethargy, muscle soreness and difficulty walking, breathing difficulties, increased water consumption and urination, and yellowing of the eyes and mucous membranes. Affected dogs might experience vomiting and diarrhea, both of which may contain blood.

Leptospirosis Treatment

Your veterinarian diagnoses leptospirosis through blood tests, including a titer test to detect the level of antibodies in his bloodstream. Severely afflicted dogs require hospitalization so they can receive intravenous fluid therapy and, if they are unable to keep food down, the insertion of a gastric tube to provide nourishment. Dogs experiencing large amounts of blood loss might require transfusions. All dogs diagnosed with leptospirosis require antibiotics, usually administered for at least a month. Because this disease is contagious to people and other animals, you must keep your dog separated from other household pets and use gloves when touching him. In fact, even his bodily fluids must be treated as hazardous waste until he recovers and your vet can confirm he is no longer contagious. Your vet can also inform you how to legally dispose of the dog's bodily fluids in your locality.