Intestinal parasites are a common cause of disease in dogs and cats. There are many types of intestinal parasites, with the most common including roundworms, hookworms and whipworms. Some types of worms can cause disease in humans, so their diagnosis, treatment and prevention is very important.

Roundworms are very common in puppies and kittens. They are large worms, growing up to several inches long. They live in the small intestine, where they absorb nutrients from their host. Some infected pets may show no symptoms, while some may have vomiting, diarrhea, and a generally unhealthy appearance. Roundworms eggs are hardy in the environment, and are transmitted by ingesting contaminated soil. Humans who accidentally ingest contaminated soil may develop eye, lung, heart, and neurologic disease.

Hookworms live in the small intestine, where they attach to the intestinal lining using sharp teeth.  Hookworms suck blood from the intestinal wall, potentially causing significant blood loss. They are transmitted through ingestion of eggs that were passed into the environment via contaminated feces, and can also be absorbed through skin. Hookworms can be infectious to humans, causing cutaneous larva migrans, an itchy skin infection most commonly seen after people walk barefoot in contaminated soil.

Whipworm infections are more common in dogs than cats. Whipworms live in the cecum, which is between the small and large intestine. Mild infection may not cause clinical signs, while severe infection may cause bloody diarrhea and even death. These worms are not usually considered infectious to humans.

Diagnosis of intestinal parasites is done by fecal testing, which identifies eggs passed by parasites in the GI tract. Testing can be performed in your vet’s office, and is usually recommended as part of every routine examination. Fecal testing is recommended four times during the first year of life, and every six to 12 months thereafter. If your pet’s fecal is positive for parasite eggs, your veterinarian will recommend a treatment based on the type of eggs identified; not all dewormers treat all parasites, so a specific diagnosis through fecal testing is necessary.

Prevention of intestinal parasite infection should start early in life. Puppies and kittens should be dewormed at two weeks of age, and every two to three weeks thereafter until they are on regular heartworm prevention. Most monthly heartworm preventatives for dogs also control many varieties of intestinal parasites, although most do not cover all varieties. Many cats are not on monthly heartworm prevention, and are therefore not protected. It is highly recommended that all cats, especially outdoor cats, be started on a monthly parasite preventative.

Prevention and treatment of intestinal parasite infection in pets is critical to prevent human infection.  People should also clean up their pets’ feces daily, and wash their hands thoroughly after any contact with potentially infectious feces or soil. Adults and children should not walk outside barefoot on any potentially contaminated soil.  Sandboxes should be kept covered when not in use. If you suspect infection of yourself or another person, please contact your physician. Visit www.capcvet.org for more information.

Dr. Kelly Sulik owns and operates Animobile Mobile Veterinary Services in Tryon, N.C. She can be reached at animobiledvm@gmail.com.

~ Dr. Kelly Sulik, DVM