Resource Center Menu

Leptospirosis in Dogs 

While no dog parent can promise their pet that they’ll never get sick, you can help protect them  from certain infections by keeping up with their preventive care and monitoring their environment carefully. Such is the case with leptospirosis in dogs. This infection is commonly caused when a pet comes in contact with infected water or urine.  

If your dog has been rolling around in a dirty puddle or had contact with a wild animal, you should be on the lookout for some common signs of leptospirosis. Read on to learn more about what leptospirosis is, how your dog can get and spread it and what to do if you notice symptoms.  

What is leptospirosis in dogs? 

Leptospirosis—sometimes called lepto or Weil’s disease—is a type of bacterial infection that, once in the bloodstream, can do serious damage to your dog’s liver and kidneys. The condition comes specifically from a bacterium called Leptospira.  

Leptospirosis can be caused by any of many strains of Leptospira. You will most commonly see leptospirosis symptoms in dogs who drank from tainted water or whose mucus membranes came in contact with the bacteria. The bacteria can also find their way into the body via a scratch or open wound on a dog’s body.  

Leptospirosis is a zoonotic disease, which means it can be spread between species, including from dogs or other animals to people. It’s just as important to protect your dog against the disease as it is to make sure they don’t spread it. Dogs should be kept away from other people and pets at the first signs of leptospirosis infections.  

How do dogs get leptospirosis? 

As mentioned above, dogs often get the disease from tainted water. This can include everything from puddles and ponds to moist soil. But this isn’t the only way to encounter the bacteria.  

Infected animals have leptospirosis in their urine, which puts any dog who comes in contact with it at risk. While your dog can be infected by other dogs, they also risk exposure by rooting through trash where an infected raccoon has urinated, playing near a rat nest or interacting with other wild or domesticated creatures.  

Thanks to the virulence of the bacteria, leptospirosis can be fairly common in dogs. Take a look at these everyday activities in which your pup could come into contact with the bacteria. 

  • Playing in a muddy field or park where stagnant water is present  
  • Running through a wooded area frequented by wildlife  
  • Spending time in a kennel with other dogs who may be infected  
  • Drinking water from a puddle or body of water that other animals also visit  
  • Hunting or sporting situations where they retrieve wildlife 
  • Running through an irrigated pasture  

Should pet parents be worried? 

How common is leptospirosis in dogs? That depends on where you live. In urban areas where dogs have little contact with wild animals and are more likely to be vaccinated, the threat is not too significant. If you live in a rural area and often let your dog off leash to explore the great outdoors, however, you should familiarize yourself with leptospirosis symptoms in dogs as well as signs of Lyme disease.  

How can I protect my dog from leptospirosis? 

While vaccines are the top recommended way of preventing lepto in dogs, they only protect against the four most common variations of the bacteria that cause leptospirosis. Even if your pet is fully vaccinated, you’ll want to keep them away from dirty water and at-risk environments whenever possible. Avoid stagnant water outdoors, discourage your dog from interacting with unknown creatures, and keep them away from areas where the urine of other animals could be present. Thoroughly cleaning wounds and scratches also helps you minimize your pet’s vulnerability to all bacterial infections, including leptospirosis. 

Leptospirosis Symptoms in Dogs 

In the early stages of leptospirosis, your dog may appear tired or lethargic and have a fever. As the infection continues, you will likely see the more serious symptoms listed below. Sadly, if leptospirosis is left untreated, it can lead to kidney or liver failure. Some dogs fight off this infection relatively quickly, however, and never experience any severe signs of illness.  

Leptospirosis symptoms in dogs can be categorized by those you might spot on your own  and symptoms that are only detectable by conducting a medical test.  

Symptoms You Can Observe at Home

  • Fever
  • Weakness, lethargy or exercise intolerance
  • Refusing food, eating less food or vomiting
  • Sudden vomiting, especially when it contains blood, is a common sign of lepto in dogs.
  • Heavy panting and/or trouble breathing
  • Pain
  • Changes in stool quality
  • Increase in drinking and urination

Keep in mind that these are just some of the symptoms of leptospirosis in dogs, but they are the one that are most likely to appear if your dog is infected. In any case, a combination of these symptoms is typically a sign that your pet is ill.  

Symptoms Observable With Testing

While you may notice symptoms of lepto using your knowledge of your dog’s normal behavior and habits, a definitive diagnosis requires a vet’s expertise. Specifically, your vet can test your dog’s blood and urine for the presence of the bacteria.  

  • A DNA-PCR test is a rapid test that can detect the DNA of Leptospira in your dog’s blood or urine. The presence of this bacteria’s DNA is often the most definitive sign that your dog has leptospirosis.  
  • Your veterinarian may also choose to do a full chemical blood profile to help rule out other illnesses or detect other bacteria. A blood test can also detect kidney and liver values issues, a common indication of leptospirosis in dogs.  
  • A full urine panel—also called a urinalysis—allows your vet to look for bacteria under a microscope. It can also allow them to detect additional illnesses and rule out other types of bacteria.  
  • A microscopic agglutination test—or MAT for short—looks for antibodies. When your dog is infected, their body creates antibodies against the Leptospira bacteria found in their blood. A high level of antibodies is a good indicator that your dog currently has an infection. If they have lower levels of antibodies, it may mean they previously had the disease.  

Your veterinarian can usually identify the bacteria quickly—particularly with the PCR test. Treatment can begin as soon as the diagnosis is confirmed.  

Common Treatments for Leptospirosis in Dogs

When it comes to leptospirosis in dogs, treatment is fairly straightforward. The most common and effective treatment is the use of antibiotics. Thankfully, this type of bacteria can be quickly killed with appropriate antibiotic therapy.  

Your veterinarian may recommend several stages of antibiotics. A common protocol includes two rounds of antibiotics, with the first  addressing the acute, immediate infection your dog is facing. The second phase of antibiotics helps address any low-grade, lingering infection that may remain after the first round of treatment.  

In addition to antibiotics, your veterinarian may also recommend fluid therapy. This treats any dehydration that your dog is experiencing. They may also prescribe an anti-vomiting medication to help them keep down food and water until the antibiotics kick in. Multivitamins can also help keep your pup’s immune system strong and help them recover more easily. 

Depending on the seriousness of your dog’s infection, you may need to complete up to four weeks of treatment. While this may sound scary or time-consuming, it ultimately helps eliminate the bacteria and signs of lepto in dogs. Protecting your dog often means safeguarding your entire family, given that the bacteria can spread from dogs to people.  

Final Advice 

We recommend getting your dog vaccinated to help protect them against leptospirosis. Petco offers vaccination services in both vet hospitals and at vaccination clinics. Leptospirosis is uncommon among city dogs, but you may have reason for concern on camping trips or while spending time in wildlife areas. If you live in the country, it’s wise to be aware of leptospirosis symptoms in your pet. If your dog spends time in a wet, marshy area or decides to take a drink out of a puddle, stay vigilant and contact your vet for advice. 

Related Articles