Autumn rain refills every puddle, ditch and lake edge in Burnaby, and dogs drink from all of them. Giardia is the parasite that most often comes back with them. It survives happily in cool, wet conditions, it takes very little to cause an infection, and the diarrhea it produces has a habit of returning.
What giardia is, in plain terms
Giardia is a single-celled parasite that lives in the intestine. Infected animals pass hardy cysts in their stool, those cysts wash into soil and water, and the next animal picks them up by drinking, licking or grooming. It takes only a small number of cysts to establish, which is why it spreads so efficiently where dogs gather.
Cool and wet is exactly what it likes. The cysts survive for weeks in cold water and damp ground, while they die off quickly in hot, dry conditions. That is why a Burnaby autumn is its best season, and why a dry August is not.
Where dogs pick it up around here
- Puddles and standing water on paths, in parks and along the trail edges after rain
- The lake edge and the shallow margins where waterfowl gather and the water barely moves
- Runoff crossing a park after heavy rain, which carries whatever was upstream
- Shared water bowls outside cafes, at daycare and at off-leash parks
- Grass and mud in busy dog areas, where a dog sniffs, licks and then grooms
- Their own coat and paws, after walking through contaminated ground
Puppies, seniors and dogs with other health problems tend to get the worst of it, and dogs who use daycare or off-leash parks meet it most often.
What it looks like at home
The classic picture is diarrhea that is soft to liquid, pale, greasy-looking and unusually foul-smelling, often with a lot of gas. It may come with mucus, and sometimes a little blood. Many dogs remain bright and keep eating, which is exactly why owners wait.
Two details catch people out. First, it is often intermittent: three bad days, four normal ones, then it returns, so it looks like the dog is recovering. Second, plenty of infected dogs show nothing at all while still shedding cysts into the environment, which is how one dog quietly reinfects a household or a park.
Weight loss over a few weeks, a puppy who is not growing well, or a dog who is genuinely flat and off food are all reasons to come in sooner rather than later.
Getting an answer
Diagnosis starts with a fresh stool sample. Bring one with you if you can, ideally from that morning. Because shedding is intermittent, one clear sample does not always rule it out, so we sometimes ask for samples across a few days or use a more sensitive test.
This matters because chronic diarrhea has a long list of possible causes, and giardia is only one. Diet, other parasites, a swallowed foreign object, food sensitivity and inflammatory conditions all look similar from the outside. Testing through our pet diagnostics is what separates them, and it avoids the cycle of guessing.
If your dog is dehydrated, vomiting as well, or very young or very old, they should be seen promptly rather than monitored. Our medical services team can assess hydration and decide what support is needed alongside identifying the cause.
Breaking the cycle
The part owners find frustrating is reinfection. A dog can be dealing with the problem successfully and then pick it straight back up from the environment, or from cysts caught in their own coat.
- Bathe your dog at the end of the course of care, paying attention to the back end, so they are not carrying cysts on their fur.
- Pick up stool immediately, in your own garden as well as on walks. This is the single most effective control measure.
- Wash bowls and bedding in hot water, and clean hard surfaces thoroughly.
- Keep them off the shared water bowl and away from puddles while they are recovering.
- Let a contaminated grass area dry out in sun where possible, and avoid taking a recovering dog back to the same wet patch.
- Carry your own water. A dog who is offered clean water regularly on a walk is far less interested in a puddle.
- Wash your hands after handling stool. Giardia can pass to people, though the strains that affect dogs most often are not the ones that usually infect us. Sensible hygiene covers it, and it matters more in households with young children or anyone whose immune system is suppressed.
What about cats?
Cats get giardia too, most often in multi-cat households and in kittens from a shelter or breeder background. The signs are similar: soft, smelly stool, sometimes with weight loss in a kitten who otherwise looks well. Litter box hygiene and prompt testing are the equivalents of the advice above.
Autumn puts several things on the ground at once around Deer Lake, and not all of them are microscopic. Our guide to slug and snail bait poisoning covers the other seasonal hazard we want Burnaby owners watching for.
Frequently asked questions
My dog drinks from puddles constantly. How worried should I be?
Most puddle drinks cause nothing, but it is a repeated exposure across a long wet season, and giardia is not the only thing carried in standing water. Carry water, teach a reliable leave, and change the habit rather than worrying about a single mouthful.
Is giardia dangerous?
In an otherwise healthy adult dog it is usually unpleasant rather than dangerous, and most recover well with the right care. It matters much more in puppies, seniors, and any pet who becomes dehydrated, where fluid loss is the real risk.
Can I catch it from my dog?
It is possible but uncommon, because the types that most often infect dogs are generally not the ones that infect people. Wash your hands after handling stool, keep children away from it, and mention it to your own doctor if anyone in the household develops similar symptoms.
My dog’s diarrhea cleared up on its own. Do I still need a test?
If it was a single episode and your dog is well, probably not. If it has come and gone more than once, if there is weight loss, or if other dogs in the house are affected, test. Intermittent diarrhea that keeps returning is the classic pattern, and a dog can keep shedding after looking better.
Does a vaccine prevent it?
There is no vaccine used routinely for this in Canada. Prevention is environmental: clean water, prompt stool pick-up, hygiene and keeping dogs out of stagnant water. If your dog is a keen puddle drinker, mention it at your next wellness services visit.
Is the lake itself the problem?
Not specifically. Any still or slow-moving water that wildlife and other dogs have access to carries the same risk, including the puddle at the end of your street. Moving water and water your dog brought from home are the safer options.
Speak to the team at Deer Lake Animal Hospital
If your dog has diarrhea that keeps coming back, phone us and bring a fresh stool sample with you.
Published by the team at Deer Lake Animal Hospital.
This article is for general educational purposes only and is not a substitute for an in-person veterinary examination or advice about your individual pet. If you have an urgent concern about your pet, contact Deer Lake Animal Hospital or your nearest emergency veterinary hospital right away.
Deer Lake Animal Hospital
6170 Kingsway #100, Burnaby, BC V5J 1H5
Phone: (604) 563-6170
Hours: Monday to Saturday 8:00 AM to 8:00 PM; Sunday 9:00 AM to 6:00 PM; statutory holidays closed