Thursday, May 14, 2015

Puddles: Potential Health Hazard for Your Dog

by Nancy Kay, DVM 

There’s a lot to be said for a vigorous walk with your dog after a heavy rainstorm. The landscape appears refreshed, the air smells great, and you and your dog get to unleash some cabin fever!

As fun as it is to watch your dog splash and play in the puddles you encounter on your walk, some caution is advised. Depending on the surrounding environment, those pools of standing water can harbor some health hazards.


Leptospirosis organisms are bacteria that thrive in wet climates. Wild animals, particularly deer and rodents, and some domesticated animals (cows, sheep, pigs) can be leptospirosis carriers. Although infected, these mammals maintain good health while shedding leptospirosis organisms in their urine.

Dogs can contact leptospirosis by drinking from water sources contaminated with urine from an infected animal. 

Puddles that have formed from rain runoff certainly qualify as such a source. A study of the prevalence of canine leptospirosis in the United States and Canada revealed that disease prevalence correlates with the amount of rainfall. The more rain, the more dogs diagnosed with leptospirosis.

Not all dogs become sick when exposed to leptospirosis, but for those that do, the results can be devastating.

Leptospirosis most commonly causes kidney failure. Associated symptoms include lethargy, vomiting, diarrhea, and loss of appetite. The liver and lungs are also targets for this disease. The diagnosis of leptospirosis is made via blood and urine testing. Successful treatment consists of antibiotics and supportive therapy such as supplemental fluids.

The leptospirosis vaccination does a good job of protecting against this disease. Talk with your veterinarian about whether or not this vaccine makes sense given where you live and the nature of your dog’s extracurricular activities.


Giardia are microscopic, protozoan organisms that live within the intestinal tracts of a variety of domesticated and wild animals. The infectious (contagious) forms are shed within the feces and readily contaminate water sources. This is one of the main reasons it is recommended that hikers and backpackers drink only filtered water. A 2012 study documented that dogs who attend dog parks are more likely to test positive for giardia than those who do not attend dog parks.

The most common symptom caused by giardiasis in dogs is diarrhea. 

Vomiting and loss of appetite may also occur. The diagnosis is made via stool sample testing. A handful of medications can be used to rid the intestinal tract of giardia. Metronidazole and fenbendazole are the two most commonly used. The diagnosis of giardia in one dog may warrant treatment of the entire household herd, as giardia is highly contagious from dog to dog. It can also be transmitted to other species, including cats and humans.


Consumption of only a very tiny amount of antifreeze can have devastating consequences for dogs. Ethylene glycol, the active ingredient in antifreeze, causes acute, often irreversible kidney failure. Symptoms typically include lethargy, vomiting, diarrhea, loss of appetite, weakness, and ultimately coma and/or seizures. The diagnosis is made based on history, urine and blood testing, and often a kidney biopsy. Unfortunately, even with aggressive and expensive therapy, most dogs suffering from antifreeze toxicity don’t survive.

Until relatively recently, antifreeze had a sweet taste rendering it all the more enticing to dogs and children. 

In 2012 antifreeze manufacturers were forced to add a bittering agent to their products. Even with the addition of a bitter taste, vigilance is required to prevent antifreeze toxicity. A small amount of antifreeze within a puddle may not be enough to deter a thirsty dog from drinking.

Antifreeze sources include open product containers and antifreeze leaks from the undercarriage of vehicles. When with your dog, be sure to avoid puddles that have formed in and around parking lots.

Take home message

My goal in telling you about the potential perils of puddles isn’t to convince you to confine your dogs indoors. Heck, my dogs hike off leash with me daily, rain or shine. Rather, my objective is to increase your awareness so that you will be mindful about where your dog drinks when out and about with you (no parking lot puddles!). I encourage you to maintain awareness of the symptoms of leptospirosis, giardiasis, and antifreeze toxicity so that, if observed, you will seek veterinary attention right away.

Does your dog have exposure to puddles?


Nancy Kay, DVM

Diplomate, American College of Veterinary Internal Medicine
Author of Speaking for Spot: Be the Advocate Your Dog Needs to Live a Happy, Healthy, Longer Life
Author of Your Dog’s Best Health: A Dozen Reasonable Things to Expect From Your Vet
Recipient, Leo K. Bustad Companion Animal Veterinarian of the Year Award
Recipient, American Animal Hospital Association Animal Welfare and Humane Ethics Award
Recipient, Dog Writers Association of America Award for Best Blog
Recipient, Eukanuba Canine Health Award
Recipient, AKC Club Publication Excellence Award
Become a Fan of Speaking for Spot on Facebook

Please visit to read excerpts from Speaking for Spot. There you will also find “Advocacy Aids”- helpful health forms you can download and use for your own dog, and a collection of published articles on advocating for your pet’s health. Speaking for Spot is available at, local bookstores, and your favorite online book seller.

Did you get your copy of Speaking for Spot yet?

If not, go get the book. It's likely the most important dog book you'll ever read.

Articles by Dr. Kay:
Reasonable Expectations: The Ability to Discuss Your Internet Research With Your Vet
Finding Dr. Wonderful And Your Mutt's Mayo Clinic: Getting Started
Even The Best Veterinarian Can Make A Mistake
A Different Way to Spay
Making Tough Medical Decisions For Your Dog: Lily's Story
If You Don't Know What A Lick Granuloma Is, Count Your Blessings!
Anesthesia-Free Dental Cleaning 
Talking Teeth 
Urinary Accidents
I Can't Believe He Ate That! Foreign Body Ingestion 
What Caused Murphy's And Ruska'sPneumothorax?
The Whole Picture: When The Test Results Don't Match What's In Front Of You 
Stop that Scratching
Veterinarians And Vaccines: A Slow Learning Curve
What is a Veterinary Specialist? 
Veterinary Specialists: Oncologist 
Veterinary Specialists: Cardiologist 
Veterinary Specialists: Internist 
Veterinary Specialists: Neurologist
Veterinary Specialists: Surgeons
Nutritional Management of Canine Epilepsy
Have a Miniature Schnauzer? Know about Sick Sinus Syndrome (SSS)  


  1. Great advice! We always take bottled water with us when hiking but sometimes it's hard to keep Haley out of the puddles when hiking off-leash. Who knows what could be in some of those puddles.

    1. We always drag water but our guys always prefer drinking from whatever source they can find on their own. Fortunately, up here we have to worry only about "natural" contaminants.

  2. Wow, this was an extremely useful article! Thank you so much for the great advice and warning about puddles. I can't wait to check out "Speaking for Spot".