Seems like lately, we have been seeing a great deal of Giardia in our puppies, kittens, dogs and cats.
Giardia is an organism that causes diarrhea in some, but not all, infected animals including humans. There are different species of Giardia, groups A-G and different groups can affect different animals and humans. For now let’s focus on our dogs and cats.
Giardia comes in two forms: A trophozoite and a cyst. A trophozoite is the mobile form of the organism that can be found in the intestines and sometimes the feces. A cyst is the resistant stage that can survive outside of the host for several months. This stage is where transmission from one host to the other occurs. Cysts survive in areas where the weather is cold and there is a good amount of moisture, like water. However, they are not able to survive in hot, dry areas.
Transmission occurs through either a fecal-oral route or transmission through contaminated water or food. Higher occurrences are found in shelters or breeding colonies, while moderately found in puppies and lesser likely in house dogs.
Clinical signs, such as diarrhea, straining to defecate, mucus or frank blood in the stool and lesser likely vomiting, can occur before cysts are shed through the fecal matter. It can take from 5-12 days in dogs and 5-16 days in cats for cysts to be identified. However, there are a good amount of dogs and cats that do not show any clinical signs.
Diagnosing Giardia can be found using microscopic fecal examination, however this can be difficult in situations where cysts may be shed on and off or they break because they are so delicate. Other reasons can be due to other foreign material that is found in fecal matter that can be mistaken for Giardia such as pollen or yeast. Other tests that are used to increase chances of diagnosing Giardia include Zinc sulfate fecal by centrifugation, fecal ELISA, IFA or duodenal fluid aspiration.
Treatment includes a number of anti-parasitics or antibiotics that is chosen by your veterinarian. Additional supportive care includes a temporary low-residue diet or fiber diet that can help control the clinical symptoms. The Giardia vaccine (which is not found in the United States anymore) has been used, but was found to not prevent the infection and not considered a core vaccine. More importantly, bathing and removal fecal material will help to prevent re-infection. Baby wipes can also be used to clean the perineal area. Please make sure to wash your hands afterwards or wear gloves because even though giardia is species specific, it can still be zoonotic to humans. After treatment, bathing and re-testing is recommended.
Also remember that just because your pet gets Giardia once does not mean that he or she cannot contract the disease again. This is why routine fecal exams are needed. You never know what is in the environment.