Leptospirosis (Lepto for short) is caused by a bacterium that attacts the liver and the kidney in both people and animals.  The cat, luckily, is one species that seems to be resistant to the bacterial infection. The Leptospires are sprirochetes that live in water and have a spiral shape with a hook on each end. People and animals bcecome infected from swimming or drinking contaminated water or in direct contact with urine from an infected animal, such as raccoons, rodents or cattle. The Lepto spirochete has an uncanny ability to penetrate unbroken skin.  Once the victim is infected, the bacteria attacks  the kidney, the liver or the blood system. Signs begin to appear four to twelve days after exposure with signs varying depending on what organ is being attacked.

If the kidneys are attacked, renal failure can result. Early signs are fever, listlessness, excessive thirst and urination progressing to kidney shut down and the inability to make urine. Often times, the urine may appear brown or reddish.

If the liver is affected, the liver is damaged and the body becomes yellow or jaundiced. There will also be vomiting, fever and general illness.

The worst form is the hemorrhagic form. The dog will have a fever and develop small hemorrhages in the skin. The disease progresses to internal bleeding and bloody diarrhea and urine. This form is often fatal.

Diagnosis is often difficult because the early signs are similar to other diseases and antibody titers do not rise early in the disease.

Treatment consists of antibiotics and supportive therapy, such as intravenous fluids and a lengthy hospital stay. The fluids from the infected dog will shed the bacterium for several weeks, so care must be taken not to expose family members or hospital staff. Antibiotics are given for a few weeks after the illness to ensure killing all of the organisms. Some dogs may have lingering kidney damage resulting in chronic renal failure.

Prevention for dogs is accomplished with vaccinations. There are 4 major strains of Lepto that the vaccines will protect for. Every now and then, there are other strains that can pop up that are not covered by vaccinations. Since dogs are more likely to be exposed,  protecting them with vaccinations will help reduce possible exposure to their human friends. The downside is the lepto vaccine can cause allergic reactions in dogs. The reactions ususually result in hives or facial swelling and can be relieved with anti-histamines. I see more reactions in the Dachshunds than any other breed for some reason. Sometimes the vaccine may also cause soreness for a few days.  I feel that the benefits of vaccinating for this disease outweighs the risks of the vaccine, especially, since my clients live in a wooded neighborhood with possibility of exposure. If your dog lives in an apartment and never goes to the woods, swims in lakes or streams,  or has exposure to garbage where rodents may get into (a common source of infection), you and your veterinarian may fore go vaccinating.