Everything You Need to Know About Giardia in Dogs

Is it a worm? Is it a virus? Is it bacteria?

Giardia is in fact none of the above. It is a protozoan – a simple, single-celled parasite that comes in 7 main categories. Different types of Giardia tend to infect particular animals whether that be dogs, cats or humans.

Left untreated, the parasite can cause Giardiasis, and that can lead to some really nasty complications. Worryingly, dogs can occasionally pass the parasite on to humans.

Find out more about how puppies can be particularly susceptible as we examine the signs and prognosis related to the illnesses this unwelcome parasite can cause.

How Dogs Pick Up Giardia

Each type of Giardia has two forms. First is a fragile feeding form, known as the trophozoite. You’ll find this in the gut of infected dogs. A resilient cystic form of Giardia gets excreted within feces. It can survive for months in the environment.

Dogs get infected when they swallow Giardia at the parasite’s cystic stage. If your dog is susceptible, Giardia will attach itself to the intestinal wall to feed. It can then divide and spread, causing damage to the intestinal wall and a range of health issues.

Scavenging and Exploring

Dogs pass on the cystic Giardia in their stools. By doing this, they can spread Giardia to other dogs or humans between 5 to 12 days after first ingesting the parasite. Mixing with infected dogs is one way your pet could pick up Giardia.

Dogs tend to often get cystic Giardia from contaminated water. They can also pick it up from eating something they shouldn’t when outdoors or somehow getting the parasites in their mouths and swallowing them. Given their propensity to examine and sniff whenever they’re outdoors, it is easy to see how this could happen quite inadvertently.

The chances of developing disease grow when large numbers of cystic Giardia are present in the environment as a result of fecal contamination.

Giardiasis is especially dangerous to puppies. Although the disease does not tend to be life-threatening, it can be when a dog’s immune system is immature.

Symptoms include diarrhea that can be intermittent or continuous. Failure to diagnose and treat the disease can cause severe weight loss and even death in the most extreme cases. Senior dogs and those with compromised immune systems are at greater risk.

Giardia Symptoms and Diagnosis

Many dogs are asymptomatic carriers and never show any signs of illness. Younger animals are more prone to exhibit clinical signs. Initially, there may be a sudden and acute bout of foul-smelling diarrhea. Other symptoms of Giardiasis include:

  • Weight loss
  • Intermittent bouts of diarrhea combined with dehydration
  • Fatty stools ranging from soft to watery with a greenish tinge & excessive mucus
  • Stools that contain traces of blood
  • Vomiting and deterioration of the coat

These kinds of symptoms can persist for several weeks until gradual weight loss is apparent.

Treatment for Giardia

Sometimes, you can see the parasites on a direct smear of the feces. If your vet suspects giardiasis, they may take a sample of the stool for analysis. In some cases, they may make a diagnosis based on medical history and suggestive clinical signs.

Your vet will typically prescribe specialist drugs designed to kill off the parasite. Courses tend to last from 3 to 10 days. Separately, they’ll also treat the diarrhea and any issues related to dehydration. It’s highly likely they’ll want to re-test your pet after 2-4 weeks.

If your pet is taking medication, clean and disinfect any potentially contaminated items every day for 2 or 3 days after your dog completes the course.

Because dogs can pass on the Giardia parasite, vets recommend that you remove and dispose of feces quickly and thoroughly. You should also bathe an infected dog regularly to remove any Giardia from their coat.

Prevention of Giardia and the Likely Prognosis

Outbreaks of Giardiasis tend to happen more in places where there are dense populations of animals. These include kennels, pet stores and animal shelters.

At home, the prevention of Giardia and Giardiasis is always the best course of action and there are some simple steps you can take that will help. Here are some of them:

  • Ensure your dog always has access to fresh, clean water
  • Keep bowls slightly above ground level
  • If Giardia poses a risk in tap water where you live, boil first or use bottled water
  • Avoid locations where there’s a chance of high concentrations of dog feces
  • Limit access to creeks, ponds and lakes

The prognosis for Giardiasis is normally good. That’s provided a dog gets treated quickly and that you adhere carefully to any instructions your vet may give you. If your dog gets a Giardia diagnosis, talk to your vet about the precautions you need to take to protect yourself and any other pets you may have.

Dogs Passing Giardia to Humans

Giardiasis is unpleasant but the chances of humans picking up the Giardia parasite from a dog are relatively low. It can and does though happen. The kind of Giardia that infects humans is not typically the same kind that infects dogs and cats.

Exercising sensible personal hygiene is what counts. So, always wash your hands with hot, soapy water for at least 30 seconds after handling dog stools. Wear disposable gloves, if possible.

Clean and disinfect all household surfaces regularly, particularly those your pets like using. Remember animals with no outward signs of Giardia infection can be carrying the Giardia parasite. They can then spread it around to places that include your home.

If you’re planning on traveling to hotspots where you think the water might be unsafe, take precautions. Avoid ice in drinks in cafés, use water purifying tablets, boil tap water and wash all fruit and vegetables with bottled water.

Always Consult a Qualified Vet

Vets can carry out a diagnosis for Giardia and provide treatment for Giardiasis. If your animal is suffering from diarrhoea, going to a vet is always a reasonable option.

Alternatively, schedule an instant video consultation with our qualified veterinarians and get tailored advice from the comfort of your home – today.

We’ve plenty of other useful pet food-related articles in our blog section. Find out here about other parasites that can infect dogs such as heartworm.

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