Intestinal parasites are common in both dogs and cats — even pets that stay mostly indoors. These parasites live in the digestive tract and can cause a range of problems, from mild digestive upset to serious illness. Some can even be passed to people (zoonotic diseases), making regular prevention and testing important for your whole family’s health.
Common Parasites We See
Roundworms (Toxocara, Toxascaris): Common in puppies and kittens. Transmitted through the environment, from mother to offspring, or by eating infected prey. Can cause pot-bellied appearance, vomiting, diarrhea, or poor growth. Zoonotic risk: Can infect humans, especially children, leading to organ or eye damage (visceral or ocular larva migrans).
Hookworms (Ancylostoma, Uncinaria): Spread by ingesting larvae or through skin contact with contaminated soil. Feed on blood in the intestines, causing anemia, weakness, and black, tarry stools. Zoonotic risk: Can cause itchy, migrating skin lesions (‘cutaneous larva migrans’) in people.
Whipworms (Trichuris vulpis): Affect dogs (rare in cats). Transmitted by ingesting eggs from contaminated soil or feces. Cause chronic diarrhea, weight loss, and sometimes bloody stools. Zoonotic risk: Rare, but possible with certain species.
Tapeworms (Dipylidium, Taenia, Echinococcus): Often acquired by ingesting fleas or rodents. Owners may notice small ‘rice-like’ segments near the pet’s anus or in bedding. Zoonotic risk: Some species can infect humans, especially children, if eggs are accidentally ingested.
Giardia: A microscopic parasite found in contaminated water or feces. Causes intermittent soft stools or diarrhea, sometimes with mucus. Zoonotic risk: Humans can become infected through contaminated water or direct contact with infected stool.
Coccidia (Isospora spp.): Most common in young pets or those from crowded environments. Spread by ingesting oocysts from contaminated areas. Can cause watery diarrhea and dehydration. Zoonotic risk: Low, but related species (like Cryptosporidium) can infect humans.
How Pets Get Infected
• Ingesting infected feces, soil, grass, or water
• Eating prey animals or insects (such as fleas)
• Transferred from mother to puppies or kittens before birth or through nursing • Contact with contaminated environments at parks, boarding facilities, or even sidewalks
Zoonotic Risks (Parasites That Can Affect People)
• Children are at highest risk because they often play outdoors and may not wash hands thoroughly.
• Parasite eggs can survive in soil for months, making yard cleanup and regular deworming critical.
• Annual fecal testing and year-round parasite prevention are the best protection for both pets and families.
How to Protect Your Pet and Family
• Routine fecal exams (at least once or twice a year)
• Monthly broad-spectrum parasite preventatives recommended by your veterinarian • Prompt cleanup of pet waste from yards and litter boxes
• Regular handwashing, especially after handling pets or outdoor play • Keep fleas under control, since they can transmit tapeworms
Schedule your pet’s fecal test and parasite prevention consultation today to keep your whole family safe!