Giardiasis is a serious gastrointestinal Infection caused by Giardia, a simple but dangerous parasite. It can be a significant cause of illnesses in dogs and humans. Here’s what to know about Giardia in dogs:

What is Giardia?

Giardia is a type of one-celled organism called a protozoan. There are a few different types of this organism, but the most common one that impacts dogs, humans, and other mammals is called G. duodenalis. This parasite can cause giardiasis, which can cause “Traveler’s Diarrhea” or “beaver fever”. It’s considered to be a zoonotic disease because it can transfer between animals and humans. It’s one of the diseases you can spread to your dog and vice versa.

This simple organism appears in two forms: cysts and trophozoites. Trophozoites are the active and feeding form. This form has flagella which are long whip-like appendages. These appendages allow them to swim throughout the intestines of a host. Trophozoites attach to the small intestine walls which cause damage and inflammation. This then leads to diarrhea and other symptoms.

Sometimes these trophozoites form into cysts, which are similar to eggs. These cysts move from the dog’s intestines and into its feces. This is where the infectious stage of the protozoan’s life cycle begins. If a dog, human, or other mammal is infected with these cysts, it is called giardiasis.

Causes of Giardia

The parasite is shed in its cystic form through the feces of an infected animal. These cystic organisms are immediately contagious. Unfortunately, these cystic parasites can stay contagious for months, depending on the right conditions. Cysts thrive in cold water and as temperatures rise, their contagiousness decreases. If the cysts are in soils, they can live up to seven weeks in cool temperatures. They can live for about a week in warmer temperatures or on surfaces.

Infection occurs when a dog ingests these cysts. This often happens when a dog drinks water contaminated with the cysts. If you’ve ever wondered if dogs should drink out of shared water bowls, this might be a good reason they shouldn’t. They can also ingest them by licking their fur that has touched soil contaminated with the cysts.

Dogs can also be infected if they eat infected poop. There are a few different reasons why dogs eat poop but most often it’s a sign of anxiety. Once a dog ingests these cysts, it can take up to 12 days for the cysts to turn into trophozoites. These trophozoites then turn into more cysts that get passed in a dog’s stool and the whole cycle begins again.

Symptoms of Giardia in Dogs

A fair amount of dogs infected with Giardia actually do not exhibit symptoms and do not usually have diarrhea or vomiting. Puppies and senior dogs infected with Giardia do tend to have diarrhea, but most healthy adult dogs do not. In healthy adult dogs without diarrhea, Giardia is usually transient and insignificant.

But if Giardia in dogs develops into a giardiasis infection, dogs do exhibit symptoms; the most common one is diarrhea which smells very bad, is worse than typical dog feces, and is often watery with a greenish tinge. Some dogs with giardiasis might only exhibit diarrhea some of the time while others might exhibit it all the time. Their diarrhea may also contain mucus.

Dogs that develop long-term giardiasis may experience weight loss. This is due to poor nutrition absorption in the small intestine as the parasite irritates the intestine walls. These dogs also may experience vomiting and lethargy. Some may even lose their appetite. If your dog exhibits any of these symptoms, you should talk to your vet. These are symptoms you should never ignore in your dog.

Diagnosing Giardia in Dogs

Unfortunately, diagnosing Giardia isn’t an easy task. It’s not as easy to identify as other parasites because the cysts are not consistently shed in the dog’s stool. Diagnosing Giardia also requires a special zinc sulfate flotation solution. Sometimes, the cysts can be seen on a direct fecal smear.

If your veterinarian suspects that your dog has giardiasis, they will take a stool sample for analysis that looks for specific antigens. Sometimes it takes a combination of tests to accurately diagnose giardiasis.

Treatments for Giardiasis in Dogs

Thankfully, there are treatments available for giardiasis. Metronidazole is one of the most common treatment options available. It is an antibiotic that is also effective for giardiasis.

Another commonly prescribed treatment is an anti-parasitic drug called fenbendazole. These drugs are given daily for up to ten days. If diarrhea or other symptoms persist, your vet may extend the treatment.

Your dog may also be prescribed anti-nausea or vomiting medication if needed. Your veterinarian will perform a follow-up test in either two to four weeks after initial diagnosis. This is just to check that your dog is not passing cysts.

What is the Prognosis for Giardiasis?

Thankfully, the prognosis for giardiasis is typically good. If your dog has health complications or is much older, they may be at a higher risk for other complications. Dogs diagnosed with giardiasis should be retested 2 to 4 weeks after treatment to see if they’re all clear.

Is Giardia Contagious to Humans?

No one wants to get giardiasis. However, the chance of your dog infecting you with giardiasis is somewhat low but still possible. To keep infection at bay, use disposable gloves when picking up your dog’s feces and wash your hands thoroughly and frequently.

Giardia in humans is most often contracted through drinking infected water, not from dogs. If Giardia is present in your drinking water, filter or boil your water. It can also be present on your food, especially vegetables grown in your soil. Make sure you wash vegetables thoroughly before eating.

3 Ways to Prevent Giardiasis in Dogs

While you can’t control every aspect of your dog’s environment, there are some steps you can take to prevent giardiasis in dogs:

1. Ensure Fresh and Clean Water Access

The most important thing you can do to prevent giardiasis in dogs is to make sure your dog has access to clean and fresh water in a bowl that is off the ground. This may reduce the chance that your dog will lap up water from puddles that may be infected.

A water fountain may also be helpful in providing fresh water, too. You can set up a feeding station for your dog so everything is in one area, making it easy for your dog to access clean water and food.

If you live in a place where Giardia is present in your water, you may need to invest in a filter that kills the bacteria. Alternatively, you can also boil your dog’s water to kill the bacteria. If you choose the boiling route, make sure your dog’s water has cooled down when you give it to them!

2. Avoid Areas With Lots of Dog Feces

Limiting your dog’s exposure to other dogs’ feces can help prevent giardiasis in your dog. These areas can often include dog parks and boarding facilities. This isn’t true for all dog parks and boarding facilities but is something you want to be aware of if you are planning to visit a specific park or use a specific facility.

If you need to board your dog, be sure to research the facility first and make sure to ask what measures they take to prevent Giardia. Doing research before boarding your dog is an important dog boarding tip.

3. Pay Attention to Hygiene

Another way to prevent giardiasis in dogs is to pay attention to hygiene. Pick up your dog’s poop as soon as possible after they go to the bathroom. This will help eliminate cysts from the environment and will protect other dogs and humans.

This is just a brief overview of what to know about Giardia in dogs. If you suspect your dog has giardiasis, make sure to schedule an appointment with your veterinarian. With the right treatment, your dog will be back to feeling normal in no time!