Nearly every dog will be impacted by intestinal parasites at some point, and chances are high that Giardia will be the one they encounter. Depending on the population studied, researchers have found around 8% to 25% of dogs carry Giardia germs, but many don’t show any signs, which makes Giardia easy to spread. Many dog owners are familiar with this parasite, but may not fully understand how Giardia is different. Our Valley Center Veterinary Clinic team shares myths and facts about canine giardiasis to help pet owners protect their four-legged friends.
Myth #1: People can get Giardia from dogs
Giardia is found all over the world and infects many different species, including humans. However, the most recent research indicates that Giardia has many different subtypes (i.e., assemblages). Each subtype is adapted to infect only one or two preferred species, which makes cross-species spread far less likely than once believed. Humans typically pick up Giardia from contaminated water sources, while dogs are infected by other dogs or the environment.
Theoretically, your dog could spread Giardia to an immunocompromised household member, including young children, seniors, or people undergoing chemotherapy, but that is unlikely, and cleaning up after your dog and ensuring the at-risk person minimizes close interactions and washes their hands immediately after handling your dog, can prevent this spread.
Myth #2: Dogs with giardiasis always develop diarrhea
Many dogs infected with Giardia develop watery diarrhea, which may be acute, self-limiting, chronic, or intermittent. Sometimes the diarrhea will continue after treatment, as the intestines try to heal themselves. Some infected dogs do not get sick at all, but can still spread the parasite to other pets, which is one reason why Giardia is so common among dogs, especially those who socialize frequently.
Myth #3: Giardia in dogs is difficult to treat
You may have heard that getting rid of Giardia in your dog can be tough, and some dogs never seem to clear the problem. Giardia medications are extremely effective—dogs who continue to have symptoms or test positive after treatment likely are reinfecting themselves. Giardia cysts (i.e., the infective form) can stick to a dog’s fur, live in the soil, or contaminate bedding or flooring in your home, where the microscopic creatures can easily be swallowed by your dog and cause a new infection. Thorough and frequent cleaning, removing stools immediately, and bathing your dog can help prevent re-infection.
Fact #1: All dogs are at risk for contracting Giardia
Social dogs are at highest risk for contracting Giardia, because the infective cysts are passed in other dogs’ stools and can stick to pet fur, or remain in pet facilities, the soil, or contaminated water. These cysts can live for months under the right conditions, waiting for their next host. To minimize the risk at daycare or boarding facilities, choose locations that use dog turf, which is easier to clean and disinfect than grass.
Social dogs aren’t the only ones at risk for Giardia. Any dog who frequents areas where other dogs have been, including forest preserves, ponds, or parks, can pick up this parasite. According to the Companion Animal Parasite Council (CAPC) prevalence maps, around 1 in 10 dogs in our county tests positive.
Fact #2: Routine parasite testing can detect Giardia cysts
When we ask you to bring us a stool sample for your pet’s annual wellness examination, we use the sample to run a fecal floatation test, which uses a special solution and preparation process to identify common parasites on a microscope slide, including Giardia cysts. Dogs can be infected with Giardia and not actively shed cysts in their stools, so if your symptomatic dog’s fecal floatation is normal, we may run more tests on their stool to identify Giardia genetic material.
Fact #3: Giardia treatments are determined on a case-by-case basis
Not every Giardia-infected pet requires treatment. Our veterinary team often recommends treatment for symptomatic infections or for pets at high risk for passing the disease to other dogs. Those pets without any appreciable symptoms who show cysts on their fecal test don’t require treatment, unless they live with immunocompromised household members. Each dog and home are different, so we’ll work together to find your pet’s best treatment plan.
Our Valley Center Veterinary Clinic team recommends annual fecal testing for all dogs and more frequent testing for social dogs and those with unexplained diarrhea. Contact us to schedule your pet’s next wellness appointment and fecal testing, or with questions about our wellness screening, preventive care, and parasite control recommendations for your furry pal.