Can dog poop make you sick? Germs and parasites in the yard

Your dog is family. Its poop is another story. Here's what the CDC and veterinary experts say about the germs in dog waste, how they reach people, and the everyday habits that keep your yard from being the problem.

Can dog poop make you sick?

Yes. The CDC says dog poop can carry germs that make people and animals sick, and that even a dog that looks healthy can spread germs. Its advice is to pick up dog poop even in your own yard, especially where children may play.

Most of these germs reach people in one of two ways:

• By mouth. Hands pick up germs from soil, toys, shoes or the dog, then touch a mouth or a snack. The CDC says roundworm eggs get into people's mouths through contaminated dirt or unwashed hands.
• Through bare skin. Dog hookworm larvae in soil or sand can burrow into bare feet and skin (CDC).

You don't even have to touch the dog. The CDC notes that places where animals live and roam can be contaminated, so you don't have to touch an animal to get sick.

What diseases can you get from dog poop?

The CDC's list of diseases dogs can spread to people includes several that travel through poop. These are the ones that matter most in a backyard:

A few details worth knowing:

• Roundworm is the big one for yards. Its eggs need 2 to 4 weeks outdoors to become infective, then can survive for months or even years.
• Hookworm leaves itchy, raised red tracks in the skin. The CDC says most people recover without treatment in 5 to 6 weeks, and that in the U.S. it's more common on the East Coast than the West.
• Campylobacter causes diarrhea, fever and cramps, and most people fully recover within 7 days. Many animals carry it without getting sick, and outbreaks have been traced to pet store puppies.
• Salmonella spreads through touching animals, animal poop and the places animals live and roam. The FDA notes that pets can shed it in their stool and saliva without showing symptoms.
• Giardia can survive for weeks to months in soil, but the CDC says you're unlikely to catch it from dogs, because the type that makes people sick usually isn't the type that makes dogs sick.

You'll also hear about E. coli. Locally, it's the bacteria the Macomb County Health Department tests beach water for. When Michigan wrote its E. coli cleanup plan for the beaches at Lake St. Clair Metropark and Memorial Park in St. Clair Shores, pet waste made its list of possible sources (Michigan EGLE). Our guide to dog poop and Lake St. Clair covers that side of the story.

How do you get roundworm from dog poop?

By accidentally swallowing its eggs. The CDC says people get toxocariasis, the infection caused by dog or cat roundworm, when they swallow dirt or food contaminated with the eggs, which reach the soil in animal waste. Puppies usually get roundworm from their mother before birth or while nursing, and the worms start laying eggs when a puppy is 3 to 4 weeks old.

Many infected people never feel sick. When symptoms do show up, the CDC lists fever, cough, wheezing, belly pain and an enlarged liver. If the parasite reaches an eye, it can cause redness, spots or flashes of light, or vision loss, usually in one eye. Most cases can be treated with medicine.

It isn't rare, either. A CDC-led national study estimated that about 5% of people in the U.S. had antibodies to Toxocara, a sign of past infection, in 2011 to 2014 (Liu and others, 2018).

Who is most at risk?

Anyone can get sick, but the CDC names four groups who are more likely to:

• Children under 5. They often touch surfaces that may have animal poop on them, put their hands in their mouths, and have immune systems that are still developing.
• Adults 65 and older, whose immune systems don't clear harmful germs as well as they once did.
• People with weakened immune systems, from illnesses like HIV, cancer or kidney disease, an organ transplant, or medicines that suppress the immune system.
• Pregnant women, who can pass certain infections to their babies.

The CDC also says severe roundworm cases are more likely in young children who have been playing in or eating contaminated dirt. If kids use your yard, our guide to keeping the backyard safe for kids has a full checklist.

How can you protect your family?

It comes down to a few habits:

1. Pick it up every time. Bag it for the trash, which is what the Macomb County Health Department recommends. Here's how often to pick up dog poop if every time isn't realistic, or let Poopy Scoops sweep the whole yard on a schedule, from $19 a visit for one dog. Get your price in about 30 seconds.
2. Wash with soap and water. The CDC says to wash after contact with dog poop, even if you use a bag, and to scrub for at least 20 seconds. Hand sanitizer with at least 60% alcohol is a backup, but it may not work as well on visibly dirty hands.
3. Wear shoes in the yard. That's the CDC's advice for avoiding hookworm.
4. Keep play areas clean. An older CDC guide for pet owners says to keep play areas, lawns and gardens free of animal feces, and to cover sandboxes when they're not in use.
5. Clean indoor accidents right away. The CDC says to disinfect the spot, use disposable gloves, and wash your hands afterward.
6. Keep your dog on a parasite plan from your veterinarian.

How do deworming and vet care help?

They stop the problem at the source. The CDC recommends having a veterinarian test and treat dogs for worms, especially young dogs and dogs that spend time outdoors, so people are less likely to run into parasite eggs at all.

Puppies need the earliest start. The Companion Animal Parasite Council, a group of veterinary parasite experts, recommends:

• Deworming puppies starting at 2 weeks of age, repeated every 2 weeks until 4 to 8 weeks old, then a monthly preventive
• Testing for intestinal parasites at least four times in a dog's first year and at least twice a year after that
• Year-round, broad-spectrum parasite control for adult dogs

Your veterinarian may adjust that for your dog's age, health and lifestyle, so ask what fits. And call the vet if your dog seems sick. The CDC lists diarrhea among the signs of illness in dogs, and reminds owners that even a healthy-looking dog can spread germs.

When should you call a doctor?

If you or someone in your family gets sick after contact with dog poop, or with soil where dogs go, call your doctor and mention the exposure. Symptoms the CDC ties to these germs include diarrhea, fever and stomach cramps; itchy, raised red tracks on the skin; cough, wheezing or belly pain; and eye redness, spots, flashes or vision changes.

Only a doctor can sort out the cause. The CDC notes that toxocariasis can be hard to diagnose because it looks like other infections, and that a provider may ask whether you've been around dirt or pet waste. Many of these infections clear up on their own, and most of the rest can be treated, but that's your doctor's call.