Common Intestinal Parasites

Routine fecal exams will detect intestinal parasites before they cause any loss of condition or serious disease in your pet.

Roundworms

Ascarids, also known as roundworms, can infect both dogs and cats. As the name implies, they are long round white worms. The three routes of infestation are directly from mother to pups via the placenta or the milk, indirectly by consuming a rodent that has roundworms encysted in the muscle, and finally by ingestion of the roundworm eggs. Typically, a pet walks in an area that has had the eggs deposited in feces. Later, the pet licks its feet ingesting the eggs. After the eggs hatch, the larvae (baby worms) migrate through the liver, lungs, and the adults live in the small intestine. These worms rob nutrition from the pet, causing diarrhea, and in young animals they can block the intestines. There is a zoonotic potential, or risk of human infestation, when humans contact either eggs and have contact with their mouth or when larva migrate through the skin, especially the feet. Children are most susceptible. This is why it is important to use good hand washing after handling animals or their feces and to pick up your dog or cats stool as soon as deposited.

Hookworms

This is a parasite which can infect both dogs and cats. There are several routes of infection. After the eggs are passed in the feces, they hatch into larvae. Animals may swallow the larvae to become infected or the larvae can actually penetrate the skin to infect the animal. The larvae can also be passed in the milk of the nursing mother to her young. The adult worm lives in the small intestine where it drinks blood. This worm can cause anemia (low red blood cell count) which in very young animals often is fatal. Hookworms also cause diarrhea and weight loss. This parasite also has zoonotic potential as the larvae can penetrate human skin. The risk of human infection is low but the risk can be made even lower by not walking barefoot in areas where animals defecate. Also, always use good hand washing after handling animals or their excrement.

Whip worms

Only dogs are susceptible to this parasite, becoming infected when they ingest whip worm eggs. The mature worm lives in the large intestines causing colitis (irritation to the colon), diarrhea, and blood loss. Dogs with whip worms frequently have loose stool, a good appetite, but cannot gain or maintain their weight. The eggs of this worm can remain viable in the soil for years, so reinfection tends to be a real problem. Most heartworm preventatives can be used to help prevent reinfection.

Tapeworms

Dogs and cats are both susceptible to tapeworms. Animals acquire this worm by ingesting rodents which have tapeworm larvae in their muscle, or by ingesting fleas which carry tapeworm larvae. Owner's will notice tapeworm segments on their pet's hair around the anus or on the stool. There is a species of tapeworm in the northwest which has a zoonotic potential, however, we do not see this type here.

Preventative Measures

1. Routine fecal examinations by your veterinary hospital.
2. Cleaning up and disposing of your pets feces immediately.
3. Good hand washing for the owner.
4. Monthly Interceptor or Sentinel tablet to help prevent hookworms, roundworms, and whip worms.

Intestinal parasites are easily diagnosed and are very treatable, but if they are undetected or ignored, they can cause your pet loss of condition, disease, and even death.
 

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