What are whipworms?

Whipworms (Trichuris spp.) are one of the intestinal parasites of dogs and (rarely) cats. They are small parasites, usually only measuring 2” or less, and have a whip-like appearance. However, despite their small size, they can be an important cause of illness.

How did my dog or cat get whipworms?

Dogs are typically infected after ingesting whipworm eggs from the environment. Once ingested, eggs mature in the small intestine, then the larvae migrate to the large intestine where they embed in the lining of the cecum or colon. Once adult worms reproduce, new eggs are passed in the stool and the life cycle of the parasite is complete. While cats can become infected with feline whipworms, they are quite rare.

Whipworm eggs are not as common in the environment as roundworms or hookworm eggs. However, once present, eggs can persist in the soil for months to years.

What are the clinical signs?

While these parasites can be asymptomatic in dogs, large numbers of worms can lead to clinical problems. Diarrhea, weakness, weight loss, and dehydration are the most common clinical signs. Some dogs can develop electrolyte abnormalities that mimic a disease called Addison’s disease, which can cause weakness and life-threatening dehydration. Cats rarely exhibit clinical signs.

How are whipworms diagnosed?

Whipworms are diagnosed by microscopic examination of your pet’s stool, and/or testing for whipworm antigens in your pet’s stool using a PCR test. Since your veterinarian is searching for eggs and shedding of eggs can be intermittent, more than one sample may be necessary to make a diagnosis.

How are whipworms treated?

Specific deworming medications such as fenbendazole or febantel must be used. Because of the long life cycle of this parasite, deworming should be repeated in 3-4 weeks and again in 3 months to eliminate the infection.

How can I prevent infections?

Eggs can survive in the environment for years. The eggs are highly resistant to most disinfectants and harsh environmental conditions. Prompt disposal of all feces is important, especially in yards, playgrounds, and public parks.

For those animals that are frequently infected with whipworms, monthly preventative therapy with Interceptor or Sentinel is necessary to prevent repeated infections. In addition, all pets should have a fecal intestinal parasite examination performed at least 1-2 times per year.

Are whipworms dangerous to humans?

No, this is a parasite of dogs and cats only, though infection in cats is incredibly rare.

Content prepared by St. Francis Animal Hospital, 1227 Larpenteur Ave. West, Roseville MN. 55113