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Leptospirosis, or lepto for short, is an infectious disease that can affect many animals including wildlife, rodents, dogs and people. It’s caused by a number of different strains of Leptospira bacteria, and can exist everywhere in the world, but is most prevalent during periods of heavy rains. It spreads through direct contact with another infected animal, and is most commonly found in soil and water. When dogs go swimming in or drink infected water, that’s when most infections occur. Lepto is rarely found in cats, but it is a zoonotic disease, which means it can be spread from animals to people, which also increased the chances of infection for both.

The tricky thing about diagnosing lepto is that any of the symptoms can be non-specific and can vary. Some of these includes decreased appetite, fever, muscle pain or stiffness, vomiting, diarrhea, conjunctivitis, difficulty breathing or even organ failure. In order to actually be diagnosed with lepto, a vet will need to consider a dog’s lepto vaccination status, their medical history, the likelihood of exposure, symptoms and their physical exam results along with blood tests. A specialized blood test may be needed like a serology test, which detects antibodies against the organism, or real-time PCR tests, which can detect the organism in a blood or urine sample.

Because of the increased risk of infection for pet parents and veterinary staff alike, treatment is started even before the test results come back because of the potential severity of lepto. Luckily, there are ways of preventing a pet from getting lepto. The best way, of course, is to take them to the vet for a vaccination of the lepto virus. While no virus can protect a pet 100% from contracting the disease, it will certainly help their chances of getting sick. Because there are multiple strains of the organism, there are steps to take to decrease the chances of getting lepto even more. This includes trying to minimize a dog’s contact with stagnant water and wildlife and carefully considering the increased risk of contracting the disease when doing certain outdoor activities including hunting and field trials.