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All About Roundworms!

Roundworms are the most common of the parasitic worm in dogs. Almost all dogs become infected with them at some time in their lives, usually as puppies. Roundworms may be contracted in different ways, making them easy to spread.

Most puppies get infected from their mother directly through the placenta, or after birth while nursing. Roundworms eggs can be picked up from the environment, they will even survive through our Canadian winter!

If a dog ingests an egg, it develops through several larval stages, migrating around the body. It will pass through the lungs, get coughed up and swallowed and become a mature worm in the intestines. In adult dogs, there are few signs but a large burden can overwhelm a puppy causing diarrhea, vomiting, weight loss, dull hair, and a pot-bellied appearance.

You may notice the adult roundworms in your dog’s feces or vomit. They will appear white or light brown in colour and may be several inches long, these eggs are microscopic.

Because roundworms can enter your dog’s body in many different ways, it is essential to keep your dog’s living area clean. This includes the environment, and, if possible, prevent your dog from eating wild animals that may carry roundworms.

To treat and control roundworms, newborn puppies should be treated every few weeks, then monthly as they get older. Fecal (stool) examinations should be conducted 2 to 4 times during the first year of life and yearly in adults. Nursing mothers should be kept on monthly preventive and treated along with their puppies to decrease the risk of transmission. Deworming will get rid of the adult worms, but the migrating larvae are not affected. This is why we need to keep treating every few weeks, many heartworm preventives also control roundworms. Ask your veterinarian about prevention and treatment choices that are appropriate for your dog.

Roundworms can pose a significant risk to humans, contact with contaminated soil or feces can result in human ingestion and infection. Roundworm eggs may accumulate in significant numbers in the soil where pets deposit feces. Once ingested, the larvae can migrate to the eye, lung, heart or brain causing significant disease in people, mostly children. Keep children away from areas where dogs may have defecated, and wash hands regularly.

Written by Effie Bruce, RVT