Kingstonist’s Wizard of Paws: What lurks beneath

During the hot days of summer, many dogs enjoy wading or swimming in the cool waters of Lake Ontario, or any of the other water bodies in the area. Photo by Tori Stafford.


Water is an essential part of life. A lot of pets do enjoy it, whether it be swimming, playing with what’s in their water bowl, or just watching it magically drip from the faucet. Yet, it can also harbour some scary things under the surface if we’re talking about those puddles or waterways outdoors.

Water-borne illnesses are no laughing matter and, in our region with so many lakes, some of them may naturally be present in the area. But we can’t forget about the puddles or watery areas created by heavy rains that then sit for a few days. While there’s some things we can’t control, we can be more aware of what our pets might be getting into to help keep them healthy.

One of the less problematic bugs is giardia (though still a problem). Giardia organisms living in the water can wreak havoc on the gastrointestinal tract causing varying degrees of diarrhea. Vomiting is rare. The stool may have a pale colour or a mucoid appearance. Fortunately, treatment is relatively simple and effective with no long term effects noted if it is treated promptly.

Fortunately, less commonly seen is leptospirosis. Leptospirosis is a bacterial disease typically spread by wildlife and through water (like that found in our beautiful cottage country) in many case, though other forms of transmission are possible. It can be a fatal condition affecting the kidneys or liver primarily and can even be spread to people, making it a public health risk. Early detection is key but vaccination is available for dogs. In a bit of good news, cases of leptospirosis are much less common than Lyme disease or other infectious diseases.

Additionally, some of the things that naturally occur in bodies of water — such as blue-green algae — can pose issues for dogs, so be sure to check for warnings of its presence through the local health unit later in the season.

You know what else comes with water and summer time?? Mosquitoes! These insects are not just a nuisance for you, but they can carry the deadly heartworm. Stagnant water areas and warmer weather in lake country make an ideal breeding ground for these bugs, but that alone does not guarantee heartworm disease being prevalent in these parts. While we do have cases of the disease in our region, many cases we see as veterinarians do come from the southern USA. But with any disease, it can spread, and that’s likely how it has made its way to Ontario. Veterinarians do recommend heartworm prevention as a way to keep the disease from becoming more prominent in our region as it is spread when a mosquito bites an infected dog or cat and then goes to bite another dog or cat, thereby passing on the parasite.

These things are not meant to scare you but we want to make sure that you take proper precautions. If your pet is a fan of water or you spend a lot of time in the outdoors, have a look what they might be getting into, update their vaccines, and use appropriate preventatives. And if your pet seems sick, don’t wait an extended period of time to get them checked out – early detection and treatment can be a lifesaver, so talk to your veterinarian if you have questions. Now go outside and enjoy the great summer ahead of us!



Dr. Ryan Llera is a small animal veterinarian at the Kingston Veterinary Clinic. Though originally from Florida, he married a Canadian (who is also a vet!) and they share their home with two cats, two dogs, two horses, and a rabbit. Dr. Llera also contributes writing to various other animal and veterinary related blogs. You can find more of his writing at, or see what else he is up to on Facebook, Instagram, or Twitter.



If there’s something you’ve often wondered or have questions about, let us know by email at [email protected].

*Please note that specific medical questions about your pet cannot be addressed and you should speak with your personal veterinarian. Disclaimer: All columns are personally written and my opinion and may not necessarily reflect those of current or former employers.

Leave a Reply

You cannot copy content from this page, please share the link instead!