Dogs and cats can become hosts to many intestinal parasites, some of which can cause
serious symptoms and/or be transmitted to people. For this reason, we follow the CDC’s
recommendation to deworm all new puppies.
We also recommend that all puppies have at least TWO negative fecal examinations over the course of their initial preventative care cycle to ensure that they are parasite free and none have been missed. Adult dogs should be tested yearly.
Finally, we recommend monthly heartworm preventatives YEAR-ROUND, as these
preventatives also contain ingredients to prevent intestinal parasites like roundworms,
hookworms, and in some cases, whipworms and tapeworms. We typically recommend products like Interceptor Plus, Heartgard and Trifexis. Talk to one of our veterinary team members to determine the best choice for your pet. Manufacturer rebates are often available for 6-12 month supply purchases.
Below is a brief description of the common intestinal parasites we encounter in practice
and will check your pet for with their routine fecal examinations:
Roundworms earned their name because of their tubular, or “round,” shape. There a
couple of different species that can affect your pup, but the most important to know
are Toxicaris canis and Toxicaris leonina.
Dogs (and cats) can get roundworms from a variety of carriers. The most common
source is other dogs; because infected dogs shed microscopic roundworm eggs in their
feces, your dog could become infected by getting too close to another dog’s poop. He or
she doesn’t even have to eat it – a simple sniff or lick is all that’s needed. Roundworms
can also be spread by other animals such as rodents, earthworms, cockroaches, and
Roundworms can be transferred to humans. Contact with contaminated soil or dog feces can result in human ingestion and infection. Roundworm eggs may accumulate in significant numbers in the soil where pets deposit feces. Once infected, the worms can cause eye, lung, heart and neurologic signs in people.
Children should not be allowed to play where animals have passed feces. Individuals who have direct contact with soil that may have been contaminated by cat or dog feces should wear gloves or wash their hands immediately.
Hookworms are the second most common intestinal parasites found in dogs, and they
are less commonly found in cats. Your pet can become infected when larvae get into
the animal’s skin or the lining of the mouth, which may happen if your pet eats or rolls
around in infected feces, for example. Cleaning up dog poop immediately can help
prevent the spread of hookworms, and some heartworm preventatives are also effective
against other parasites like hookworms.
Once inside an animal, hookworms actually bite into the intestinal lining and suck blood,
and infections can result in potentially life-threatening blood loss, weakness, and
malnutrition. Plus, hookworm infections are zoonotic, and can be passed to people. In
humans, the larvae produce severe itching and tunnel-like, red areas as they move
through the skin and can cause intestinal problems if eaten.
The whipworm is one of the four most common intestinal parasites of dogs. Whipworms
reside in the cecum, which is inside your dog’s body where the small intestine and largeintestine meet. Dogs become infected with whipworms by swallowing infective whipworm eggs in soil or other substances that may contain dog feces.
Dogs that are infected with a few whipworms may not have any signs of infection. More
severe infections can cause bloody diarrhea and severe disease.
Tapeworms get their name from the fact that they look like — you guessed it — tape.
The body of the tapeworm is segmented up to its neck. Its mouth is filled with six sets of
teeth that the parasite uses to attach itself to the intestinal lining. Once it’s attached, it
moves in permanently and starts stealing its meals from your pooch. Tapeworms are
usually transmitted when a dog digests a flea during grooming. Dogs can also get
tapeworms by ingesting the eggs shed by other animals or by hunting flea-infested
Giardia is a microscopic, protozoan parasite (but not a worm!) that causes inflammation
of the intestinal tract and subsequent diarrhea that can be very serious for both pets and
people. It has been referred to as backpackers’ disease because of the risk of exposure
when hiking. Giardia is transmitted by oral ingestion of water or food that has been
contaminated by stools of infected people and animals. Acute infection after exposure
can last from 1-2 weeks. The clinical signs of Giardia in animals and people are very
similar and may include:
Greasy stools that tend to float
Stomach or abdominal cramps
Upset stomach or nausea/vomiting
Dehydration (loss of fluids) and weight loss
Coccidiosis is a disease caused by the tiny, single-cell pests, coccidia. These parasites
can live in the wall of your dog’s intestines. They are most common in puppies, but can
still infect older dogs and cats, as well. Our canine friends can become infected byswallowing dirt or other things in an environment that is contaminated with coccidia-
infected feces. If your dog is infected with coccidia, the symptoms can vary. In adult dogs, there may be no signs of infection, while in puppies the symptoms can be more
serious. The most common symptom is diarrhea; in severe situations, the diarrhea can
be accompanied by blood in the stool.
If you have any questions or concerns about intestinal parasites and your pet, please speak to one of our team members! If your pet has diarrhea or you’d like to have their fecal sample checked for parasites, check out our blog on info and tips for collecting and submitting a sample!