Leptospirosis

Melissa Evans LVT, CVT, VTS(ECC) for VetCandy LLC.

Leptospirosis is a common and dangerous bacterial disease that affects animals as well as people. Leptospirosis, or Lepto for short, is considered a zoonotic disease. A zoonotic disease is any disease that can be passed from an animal to a human, or from a human to an animal. Understanding how lepto is spread and how to prevent infection can help protect your pet and yourself.

Leptospirosis is caused by a spiral shaped bacteria known as a spirochete. There are 21 different species of spirochetes in the genus Leptospira that cause leptospirosis. These spirochetes are transmitted via the bodily fluids of infected animals, most commonly urine, but also saliva and blood. Wildlife such as deer, mice, rats and raccoons, are common reservoirs. An animal is infected when it comes in to direct contact with any of the bodily fluids from an infected animal. Infection may also be caused via indirect contact, from contact with something that has been contaminated with the bacteria. We often find contaminated urine from wild animals in lakes, streams and even puddles.

Lepto is most commonly recognized in wooded areas, and higher occurences of infection are seen with heavy rainfall, warmer temperatures and flooding, making outbreaks of the disease seasonal in some parts of the world.

Not long ago there was an outbreak in New York City from rats that had been infected with leptospirosis. It is extremely important to be careful if you are out and about hiking or camping with your dog and not to let them drink out of stagnant lakes and puddles.

Clinical disease is common in wildlife and dogs, but rare in cats. Leptospirosis affects the kidneys and liver causing organ damage.  This damage can lead to organ failure and possibly death.

Symptoms of Lepto can be fairly vague and non-specific. They usually start with lethargy and  fever. As the infection progresses vomiting, diarrhea, decreased appetite, increased water intake and therefore urination can be seen. Your pet’s urine may also appear very yellow. He may also have abdominal pain and possibly jaundice - yellow mucous membranes. If you have any concerns about your pet you should bring them to the veterinarian to be evaluated right away.

How will my veterinarian diagnose my pet?

Diagnosis of leptospirosis is two fold. Your veterinarian will take a full history of your pet, be sure to tell them if you have been in a wooded area  or if your animal has been drinking out of puddles. They will also perform a full physical exam and run blood work to rule out any other conditions that may have similar symptoms.

There are two main tests that are run to check for leptospirosis. The first one is known as a snap test. This is a quick antibody test that can be run by your veterinarian in clinic if they suspect that your pet has leptospirosis. These tests are very reliable and can detect infection early on in the disease process.

The other test that is often run is the Polymerase Chain Reaction (PCR) Assay. This is the most commonly used test and many veterinarians will run both an in house snap test and send out the PCR to a lab to confirm the results. This test does need to be submitted to  the lab for testing before antibiotics have been started or the results will be corrupted. The PCR has a quick turnaround time and is a very reliable test for lepto.