Pet Wellness Guides > Leptospirosis in Dogs: What Pup Parents Need to Know

Leptospirosis in Dogs: What Pup Parents Need to Know

Posted: 11/06/2023 | BY: Erin Cain | Categories: Uncategorized

If you’re a pup parent, it’s essential to be aware of leptospirosis and its dangers to your furry friend. This illness is caused by bacteria and can be deadly if not treated properly. This article will discuss what leptospirosis is, how it’s transmitted, and the symptoms you should look out for. We’ll also cover treatment options and ways to prevent your dog from getting sick. Keep reading for more information!

A pug hikes in the woods.

What is leptospirosis in dogs?

When you see your dog drinking from puddles or streams, or swimming in a pond, it’s easy to forget that both activities put them at risk for contracting leptospirosis.

Leptospirosis is a bacterial infection that can cause severe illness in dogs, other pets, animals, and people. Spiral-shaped bacteria called Leptospira, which live in warm, wet soil or water, cause this disease. As a zoonotic disease, leptospirosis can be passed from animals to people. The occurrence of human leptospirosis in the United States is most common due to recreational activities involving water. It’s also possible for the infection to result from contact with an infected pet. However, this form of transmission is much less common.

There are many strains of Lepto bacteria — at least 230 that scientists have identified— and each has its own unique capabilities for causing infection in canines, humans, and other animal hosts alike. Thus, dog owners need to be aware of this disease for their dog’s sake.

Left untreated, leptospirosis can cause potentially irreversible organ failure, leading to death. Although leptospirosis is more commonly found in rural areas, warm climates, and places with high annual rainfall, it can happen anywhere. Unfortunately, this infectious disease is on the rise due to population growth, climate change, and habitat overreach, leading to more infections in dogs in urban environments. Early in 2022, New York City experienced a leptospirosis outbreak in Brooklyn that resulted in the deaths of several dogs.

A Golden Retriever puppy lays in the grass.

How can dogs contract leptospirosis?

Leptospirosis is a zoonotic disease transmitted through direct contact or indirect exposure to the pathogen via environmental exposure from infected animals. Leptospires can enter the body through any opening in the skin, including the mouth, nose, or eyes, or through wounds, scrapes, and cuts. Dogs can become infected through any of the following means:

  • coming into contact with contaminated water, soil, bedding, or food
  • coming into contact with infected urine or urine-soaked soil
  • being bitten by an infected animal
  • eating infected carcasses or infected tissues
  • drinking contaminated water from rivers, lakes, streams, or ponds
  • through breeding, where the infection spreads through the placenta of the mother dog to her puppies

The risk factors for leptospirosis in dogs residing within the United States include exposure to contaminated water, roaming on rural properties (because of possible infection by wildlife or farm animals), and contact with rodents.

Leptospira can be transferred from one host to another through blood, urine, or other body fluids. They can multiply in the bloodstream as it moves through different organs until reaching the kidneys and other tissues, where they will continue reproducing. From the kidneys, Leptospires are carried into the urine. Then, they are shed back into the environment. Dogs can then become infected through direct or indirect contact with other dogs, wild animals, or people.

Without treatment, an infected dog runs the risk of the following morbidities:

  • Vascular damage (thrombocytopenia): This damage interferes with liver function and can lead to kidney failure. Thrombocytopenia also causes hemorrhages and coagulatory abnormalities.
  • Severe kidney and liver damage: These conditions may cause acute renal failure and chronic hepatitis.

Dogs who show any symptoms of leptospirosis should be taken to a veterinarian clinic immediately.

A Siberian Husky lies on the grass.

What are the symptoms of leptospirosis in dogs?

The clinical signs of leptospirosis infection in canines vary depending on how much damage the bacteria have done to your dog’s organs and tissues. Some will only show mild or moderate symptoms, while others may experience more severe effects that cause death. And some dogs never show any symptoms of infection at all. Here are the clinical signs of leptospirosis infection in those dogs who do experience symptoms:

  • shivering
  • fever
  • muscle tenderness
  • reluctance to move
  • stiffness
  • loss of appetite
  • anorexia
  • weight loss
  • jaundice
  • depression
  • dehydration
  • diarrhea and vomiting
  • abdominal pain
  • increased thirst
  • increased urine production
  • painful inflammation of the eyes
  • kidney or liver failure
  • bleeding disorders (i.e., nosebleeds, blood in urine, stool, or vomit)
  • swollen legs
  • excess fluid in the abdomen, legs, or chest
  • respiratory distress and lung disease
  • bruising

Leptospirosis is a severe illness and potentially life-threatening bacterial infection that can lead to irreversible liver or kidney failure, acute kidney injury, significant bleeding problems, and death. If you notice any of these signs in your dog, consult a veterinarian immediately as they may be able to treat the infection before it’s too late.

After recovering from leptospirosis, a dog will only be immune to the type of leptospira that caused its initial infection. Unfortunately, if dogs are exposed to other leptospira bacteria, they are likely to become infected again.

A mixed breed dog stands in the water.

How is leptospirosis diagnosed?

When a dog is infected with leptospirosis, urine and blood tests confirm the presence of leptospira. Your veterinarian may order additional leptospira tests to verify the leptospira bacteria or identify antibodies, the proteins the body produces as an immune system response to the infection.

Therefore, diagnosing leptospirosis depends on blood chemistry, urinalysis, and leptospira testing. Your veterinarian can provide you with exact details based on your dog’s results.

A hound dog stands in a pond.

Treatment for leptospirosis in dogs

The first step to treating leptospirosis is almost always antibiotics combined with supportive care. Typically appropriate antibiotic therapy is accompanied by intravenous fluids. Your veterinarian may also prescribe supportive medications to decrease vomiting and diarrhea or manage the effects of liver and kidney damage.

To give a dog the best chance at survival, pet parents should seek veterinary attention and treatment as soon they start showing signs of leptospirosis. When treated early with aggressive treatment, infected dogs have an 80% chance of survival; however, their liver and kidney functions may be permanently damaged.

Take the following precautions to protect yourself if your dog has been diagnosed with leptospirosis:

  • Avoid contact with your dog’s urine and stool;
  • Have your dog to urinate away from standing water and away from areas other animals, dogs, or people frequent;
  • For indoor accidents, wear gloves and clean the area quickly with a household disinfectant;
  • Wear disposable gloves when handling and cleaning your dog’s bedding;
  • Wash and disinfect your hands after holding or being near your dog.

Consult your physician if you have questions about leptospirosis. If you are immunocompromised due to medications or cancer treatment or are pregnant, talk to your doctor first before proceeding with your dog’s treatment.

A French Bulldog stands in a puddle of water.

How can you prevent leptospirosis?

One of the best ways to prevent your dog from getting leptospirosis is by making sure they don’t have access to or contact any contaminated water. Additionally, sanitize the environment in and around your home by eliminating access to food and garbage, which will reduce the number of rats and raccoons which may be carrying this bacteria.

If your dog is going to be outside for any time, make sure they are vaccinated against leptospirosis. The lepto vaccine is the best way to prevent this disease. Recent medical advancements have led to a second-generation, four-way shot protecting against four different kinds of leptospirosis. This particular shot causes fewer reactions in canines than previous versions of the vaccine.

It’s important to note that vaccination does not always prevent infection. Still, it tends to make the disease much milder if a dog becomes infected. Inoculations can help dogs live long, healthy lives by preventing diseases like leptospirosis, which are potentially life-threatening in their untreated form.

While the leptospirosis vaccine is an excellent way to protect your dog from this infection, you should always discuss the vaccine with your veterinarian. This decision will depend on many factors, including your dog’s lifestyle, environment, and how often they are outdoors. Another consideration is whether there have been any leptospirosis cases or outbreaks in your area recently that might affect your pup. Ask your veterinary staff whether this vaccination is suitable for your dog.

Two dogs sniff noses at a dog park.

Protect your pup from unseen dangers.

As pet parents, you’ll do everything to protect your dog from disease and illness. Unfortunately, sometimes despite our very best efforts, our dogs become sick anyway. That’s when the costs of emergency or multiple veterinary visits for your dog’s treatment really add up. Protect your dog with a pet insurance plan that guarantees the best veterinary care without breaking your bank account. A dog health insurance plan can reimburse you for up to 90% of your dog’s veterinary costs.

At Pet Insurance Review, we’re all about finding the best policies from the top pet insurance providers in the country. Simply get a free quote now, and let us do the rest!


  1. Ko, A., Goarant, C., Picardeau, M. (2009). Leptospira: the dawn of the molecular genetics era for an emerging zoonotic pathogen. Retrieved from
  2. Klein, J. (2022). NYC Leptospirosis Outbreak in Dogs: What to Know. Retrieved from
  3. Campbell Thornton, K. (2021). Why leptospirosis incidence are on the rise. Retrieved from
  4. Fondren, P., Zraick, K. (2022). What New York Dog Owners Should Know About Leptospirosis. Retrieved from
  5. Kruzer, A. (2022). Thrombocytopenia In Dogs. Retrieved from
  6. NYC Health. (n.d.). Canine Leptospirosis FAQs for Dog Owners. Retrieved from
  7. Animal Clinic of Council Bluffs. (2020). The Low Down on Leptospirosis in Dogs. Retrieved from
  8. Animal Clinic of Woodruff. (2017). Leptospirosis: The summertime, water dog infection. Retrieved from
  9. McCalley, L. (2020). Leptospirosis Vaccine for Dogs. Retrieved from

The information contained on this blog is intended for informational and educational purposes only and should not be construed as medical advice. It is not a substitute for professional veterinary care. Always consult with your veterinarian before making any changes to your pet's health care or treatment plan.

The authors of this blog are not veterinarians and do not claim to be experts in pet health. The information provided here is based on our own experiences and research, as well as information from reputable sources. However, we cannot guarantee the accuracy or completeness of this information.

We encourage you to do your own research and consult with your veterinarian before making any decisions about your pet's health.

Get a quote today

Leave a review