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Leptospirosis is a zoonotic disease transmitted by the spirochete bacterium Leptospira spp. The bacteria is shed in the urine of an infected host which can include mice, raccoons, skunks, deer, sheep, dogs and even humans. The bacteria remains viable in the environment as long as it is moist, so it is most prevalent in Florida during the wet summer months.

Dogs most commonly come in contact with the bacteria by licking urine off the grass, or drinking from puddles in the yard that have been contaminated with infected urine. Clinical signs are jaundice (yellowing of the skin, eyes), bloody urine, fever, lethargy, vomiting, inappetance, and kidney failure, and death. The incubation period in dogs is 2-20 days. In humans the signs include lethargy, fever, severe headache, chills, muscle aches, vomiting, diarrhea, and jaundice, and death. The incubation period in humans is 4-14 days. People who are exposed to contaminated water such as surfers, and professionals who are exposed to contaminated urine such as veterinarians, and slaughterhouse workers are most at risk.
Diagnosis is made from blood samples and fresh urine in early infections.

Treatment if caught early, is with antibiotics such as penicillin, and doxycycline. Penicillin is given initially to control shedding of the bacteria in the urine, then doxycycline is used to get rid of the carrier state. The key is prevention. There are no vaccines available for humans, but there are effective vaccines for dogs. The canine leptospirosis vaccine contains the 4 most common serovars, and is included in most distemper/parvo vaccine combination protocols. There are many veterinary practices that do not include leptospirosis vaccine in their annual vaccination protocol and 3 years ago we had 4 cases of leptospirosis.

Zoomed in picture of leptosporia under microscope.

Two of the dogs were not current on any vaccines, and the other two came from veterinary hospitals that did not include leptospirosis in their vaccine protocol. We were able to save two of the dogs. This also posed a significant risk to the owners’ health. We advised them to avoid contact with their dogs’ urine and confine the area where their dogs urinate to limit the area that could become contaminated. This past month we had 2 young dogs with unexplained kidney disease that were had not been vaccinated against leptospirosis by their previous vets and their owners spent some anxious moments while we waited for the leptospirosis titers to come in.

We strongly recommend that all dogs be vaccinated against leptospirosis annually to prevent this potentially fatal disease.

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