The chances of getting worms from your dog are low if you practice basic hygiene and keep your pet on a regular deworming schedule, but the risk is not zero. Several types of dog parasites can infect humans, and certain groups, especially young children, face meaningfully higher odds. The transmission almost never happens through direct contact like petting or being licked. Instead, it requires exposure to contaminated soil, accidentally swallowing microscopic eggs, or in one case, swallowing an infected flea.
How Dog Worms Actually Spread to Humans
You won’t catch worms from your dog the way you catch a cold. The parasites don’t jump from animal to person through casual contact. Each type of worm has a specific route into your body, and understanding those routes is what makes prevention straightforward.
Roundworm eggs leave your dog’s body in feces, but they aren’t immediately infectious. They need 2 to 4 weeks sitting in soil or sand before they develop enough to cause an infection. That means fresh dog poop isn’t the immediate threat. The real risk comes from soil where old, unremoved feces have broken down and left behind mature eggs. You get infected by accidentally swallowing contaminated dirt or food, which is why children who play in soil and put their hands in their mouths are the most vulnerable group.
Hookworms take a different path entirely. Their larvae live in contaminated soil and burrow directly through bare skin, typically on your feet or legs. Walking barefoot or sitting on ground where an infected dog has defecated is the primary exposure route.
Tapeworms are the oddest case. The dog tapeworm can only infect you if you swallow an infected flea. This happens most often with small children who have close face-to-face contact with flea-infested pets.
Which Worms Pose the Biggest Risk
Three parasites account for nearly all dog-to-human worm transmission: roundworms, hookworms, and tapeworms. They cause very different problems in the human body.
Roundworms
Roundworm infection (toxocariasis) is the most concerning. Because humans aren’t the parasite’s intended host, the larvae can’t complete their life cycle. Instead, they wander through body tissues, causing damage along the way. When larvae migrate through the liver, lungs, or muscles, the condition is called visceral larva migrans. It causes fever, coughing, weight loss, rashes, and an enlarged liver. This form occurs mostly in preschool-aged children. In rare but serious cases, larvae reach the heart, lungs, or brain, which can be life-threatening.
When a larva reaches the eye, it causes ocular larva migrans, which typically affects one eye and can lead to permanent vision loss. This form tends to show up in older children and young adults. Granulomas caused by the larvae have sometimes been mistaken for eye tumors.
Hookworms
Dog hookworm larvae that penetrate human skin cause cutaneous larva migrans. You’ll see raised, red, winding tracks on the skin where the larvae are burrowing, along with intense itching. The condition is uncomfortable but usually stays in the skin and resolves on its own or with treatment. In rare cases, some hookworm species can penetrate deeper into the intestines, lungs, or eyes.
Tapeworms
Human infections with the dog tapeworm are uncommon and generally mild. Children are the most frequently infected, likely because of their close physical contact with pets and the greater chance of accidentally swallowing a flea during play.
Who Faces the Highest Risk
Young children, particularly those under five, are far more likely to become infected than adults. They play on the ground, dig in dirt, put contaminated hands and objects in their mouths, and have closer face-to-body contact with pets. The most serious forms of roundworm infection occur predominantly in preschool children.
People who work closely with animals and their feces also face elevated risk. Shelter workers, veterinary staff, and kennel employees have constant exposure to potentially contaminated environments. Anyone who regularly handles soil, such as gardeners, should also be aware of the risk, particularly if dogs have access to the same areas.
What Drives the Risk Up or Down
A few specific factors determine whether your household falls on the high or low end of the risk spectrum.
The single biggest factor is whether your dog carries an active parasite infection. Puppies are especially likely to harbor roundworms and hookworms, and they shed enormous numbers of eggs. An untreated puppy defecating in your yard is a fundamentally different risk scenario than an adult dog on year-round parasite prevention.
The second factor is how quickly you clean up after your dog. Since roundworm eggs need 2 to 4 weeks in the environment to become infectious, picking up feces promptly eliminates the vast majority of the risk. A yard where dog waste sits for weeks or months becomes a reservoir of mature, infectious eggs that can persist in soil for years.
Flea control matters too, since fleas are the required middleman for tapeworm transmission. A dog with an active flea infestation in a household with small children creates a realistic, if still uncommon, path to human tapeworm infection.
How to Minimize Your Risk
Regular deworming is the foundation of prevention. The Companion Animal Parasite Council recommends that all dogs receive year-round parasite prevention with products that target roundworms, hookworms, and other parasites with the potential to infect humans. Many monthly heartworm prevention products also cover intestinal worms and fleas in a single dose, which simplifies the process considerably.
Puppies need more aggressive treatment. They should be dewormed starting at two weeks of age and retreated every 2 to 3 weeks until they’re 8 to 12 weeks old. Pregnant and nursing dogs should be dewormed every two weeks as well, since they can pass roundworms to their puppies before birth.
On the hygiene side, the steps are simple but they matter:
- Pick up dog feces immediately from your yard, garden, and any public space. Don’t let it sit and mature.
- Wash your hands after handling soil, cleaning up after your dog, or any direct pet contact. Make sure children do the same.
- Cover sandboxes when they’re not in use to prevent cats and dogs from using them as a litter box.
- Wear shoes outdoors in areas where dogs or cats defecate, to block hookworm larvae from reaching your skin.
- Discourage children from eating dirt or playing in areas that may be contaminated with animal waste.
If your dog has diarrhea or a known parasite infection, keep them away from dog parks and public areas until the issue is resolved. Keeping your dog leashed in public spaces also reduces their chance of picking up parasites from contaminated ground or other animals’ feces, which in turn lowers the risk they bring something home to your family.