Spending quality time cuddling and playing with your four-legged companion is one of the many benefits of pet ownership. Our pets are our constant companions, workout partners, and often our nap buddies, but this close relationship should not include sharing hitchhiking pests that may invade our pets. Regular preventive veterinary care and monthly parasite control are vital to keep most parasites at bay, yet some organisms can still invade your pet. Parasite infestations can make your pet sick, and can be deadly in some cases.

Most pet owners are familiar with external parasites such as fleas, or internal parasites such as tapeworms. However, pets can also be infected with microscopic parasites that are resistant to common pet parasite control medications. Our Groves Veterinary Clinic team explains two unique parasites that may be lurking in your pet’s environment, and parasite prevention methods for your pet.  

Coccidia in pets

Coccidia are single-celled, microscopic protozoan organisms that can infect the intestinal tract of animals and humans. There are numerous species of this parasite, and people are generally not affected by the same coccidia species that infect and sicken your dog or cat. However, pets can carry certain coccidia species that may cause illness in people. 

The Isospora coccidia species is most common in our companion animals, with two species that commonly infect cats, and four that can infect our canine friends. Young puppies and kittens are most susceptible to coccidia infection because their immune systems are not fully developed. Adult, chronically ill pets also can be affected because their immune system is weakened from a disease, such as cancer or kidney failure.

  • The infection — Pets are most commonly infected from ingesting an immature coccidia parasite, or oocyst, that is present in contaminated soil or feces. Ingestion of a secondary host such as a fly, mouse, or insect can also infect a dog or cat. Once ingested, the oocyst breaks open and releases sporozoites, which attach to the intestinal wall of your pet’s gastrointestinal (GI) tract. These sporozoites continue to mature and reproduce, which destroys your pet’s GI lining. The infection can occur from 3 to 11 days following ingestion of the immature coccidia.
  • The signs — Many animals will have a subclinical infection and not show any signs, but pets who become sick may have the following:
    • Watery diarrhea
    • Abdominal distention
    • Vomiting
    • Dehydration
    • Lethargy 
    • Weight loss
    • Fever
    • Decreased appetite
  • Diagnosis and treatment — Our veterinarian can detect this parasite with a standard fecal test during your pet’s wellness care examination. Pets who do not show any clinical signs may not need treatment. Pets who are sick with coccidia will be treated with a specific antibiotic, and may require medication for up to one month. Additional treatment may include fluid therapy to correct dehydration, anti-nausea medication, and a specialized diet.  

Giardia in pets

Giardia, like coccidia, is a single-celled microscopic protozoan parasite with characteristic flagella that feeds on the GI lining of many species, including dogs, cats, wildlife and humans. There are numerous species of giardia, which is commonly known as the culprit of traveler’s diarrhea in humans. Young pets and chronically ill adult dogs and cats are most at risk for illness from giardia infection. This parasite has two forms—cystic and trophozoite. The cystic form can survive in the environment for several months waiting for a host, which could be your puppy or kitten. 

  • The infection — Pets become infected by ingesting feces, sniffing fur, ingesting soil, or drinking water contaminated with giardia cysts. Once ingested, the cystic form travels through the GI tract and transforms to the trophozoite, or feeding stage, to attach to the intestinal wall and feed off of your pet’s nutrients.
  • The signs — Infection can lead to intestinal wall damage, and cause the following signs:
    • Vomiting 
    • Watery diarrhea
    • Green-tinged or bloody diarrhea 
    • Mucoid diarrhea
    • Weight loss
    • Dehydration
    • Rounded abdomen
    • Lethargy
  • Diagnosis and treatment — Giardia is not easily detected in routine fecal tests. If your pet is showing giardia signs, our veterinarian may recommend a specialized fecal test to detect giardia cell proteins, or antigens. Pets with giardia-associated illness are commonly treated with antibiotic and antiparasitic medications. Additional treatments may include fluid therapy, anti-nausea medication, and a specialized diet. Following treatment, your pet will need additional testing to ensure the giardia parasites have been cleared from their GI tract. 

Protozoan parasite prevention in pets

Pets infected with protozoan parasites are at risk for reinfection from their environment. Humans can also be infected with giardia, so ensure you wear gloves when cleaning or handling your pet, until the infection has been cleared. Additionally, follow these prevention measures:

  • Immediately remove and dispose of feces
  • Clean your pet’s bedding and living spaces with dilute bleach, or a quaternary ammonia cleaner, like lysol
  • Bathe your giardia-infected pet frequently, since cysts can live on their fur 
  • Prevent your pet from ingesting feces, wildlife, groundwater, toilet water, or soil
  • Schedule regular preventive care visits
  • Seek immediate veterinary care if your pet shows signs of a protozoan infection

Protozoan parasite infections can be deadly without treatment, especially in young or immunocompromised pets. Call our Groves Veterinary Clinic office, and schedule an appointment if you suspect your pet has an intestinal parasite infection.