Top 10 Pet Parasites

A veterinary technician must always be on the lookout for the wide assortment of parasites that can infect a pet. From dogs and cats to rabbits and hamsters, vet techs must understand how parasites can affect all species of animals. These parasites live in various organs and body systems and can spread through a variety of means, causing major problems for the host animal.

Here’s an overview of the top 10 pet parasites every veterinary technician needs to know – and why this knowledge is so important for professionals in the field.   

Roundworms are the most common parasitic worms found inside cats and dogs, according to Pets & Parasites, a website maintained by the Companion Animal Parasite Council (CAPC). Roundworms, also known as ascarids, are a genus of parasitic nematode worms. Exposure can occur in a variety of ways, including transmission during birth from mother to offspring in dogs, from drinking worm larvae while nursing, ingestion of larvated eggs from a contaminated environment (such as soil), and consumption of other vertebrate hosts that have ingested larvated eggs.

Tapeworms are a type of segmented flatworm. A tapeworm usually has a head with suckers or muscular grooves that help it attach itself to the host’s intestine. Animals can get tapeworms from fleas, mice, and other rodents.

Adult hookworms live in the small intestine, where they shed eggs through feces into the environment, then develop into larvae. Pets then pick up the larvae from the contaminated environment, via either larval penetration of the skin or ingestion of infected hosts.

Named for their characteristic whip-shaped bodies, whipworms inhabit the large intestine and pass their eggs through feces. Whipworms in domesticated cats in North America are rare. These parasites are resilient to desiccation, temperature extremes, and even ultraviolet radiation, so multiple-step treatment is often required to ensure complete elimination of these parasites.

Heartworms live in the host’s heart and travel through the bloodstream to spread throughout the body. Parasitic infection of the lungs is fatal.

Lungworms settle in the host’s windpipe and lungs, causing serious respiratory problems. The pet becomes infected after drinking contaminated water or eating transport hosts, such as snails, slugs, rodents, and birds. Dogs that spend time in the woods or in fields are at high risk for lungworm infection.

Liver or blood flukes are flatworms that feed on blood. The parasites travel through the bile ducts and gallbladder, depositing eggs into the host’s intestines.

Stomach worms live in the host’s stomach. Pets may become infected with these parasites after eating grubs, beetles, or other feces-eating insects.

Threadworms enter the system through the skin, multiply through the bloodstream, live in the intestines of their host and spread through feces. In severe infections, threadworms can enter the respiratory and digestive tracts of their hosts.

Ringworms are not actually worms at all but a type of fungus that can infect the skin, hair and nails. Ringworms can spread through direct contact with an infected animal or indirect contact with bedding or dishes.

The good news is that treatments are available for pets infected with these worms. And as a veterinary technician, you can help pets heal from these infections while preventing further spread. If you’d like to take the first steps towards a career in the veterinary field, click here to learn more about Penn Foster College's Veterinary Technician program.

Vet Tech Corner is a regular series designed to educate pet owners and spread awareness of common pet issues. If you’re interested in learning more about the veterinary industry and how you can take the first steps towards a career in the field, check out Penn Foster’s online Veterinary Technician program.