Have you ever been out for a walk and as you take the next step you feel the slippery poop under your foot?
It’s not just nasty. Besides the mess and smell, it is potentially contagious. That’s why warnings have been posted in some places reminding pet owners to “restrain your dog” and scoop up their poop, with warnings that pet feces can spread disease.
As a primary care veterinarian for small animals, I deal with diseases from dog and cat feces on a daily basis. Feces represent potential zoonotic hazards, meaning they can transmit diseases from animals to humans.
The reality is that waste that ends up in the ground, whether in a neighborhood, on a hiking trail or at a dog park, can spread life-threatening parasites not only to dogs and cats, but also to wildlife and people of all ages. In a 2020 study, intestinal parasites were found in 85% of off-leash dog parks in the United States.
Although human diseases caused by soil-borne parasites are considered uncommon in the US, they are estimated to infect as many as a billion people worldwide. Signs reminding you to clean up after your pet don’t just try to keep public spaces clean; they urge you to help protect the health of your community.
The impact of abandoned poop on people
Common dog feces parasites include hookworms, roundworms, coccidia and whipworms. Hookworms and roundworms can thrive in a variety of species, including humans.
Their microscopic larvae can enter your body through tiny scratches in your skin after contact with contaminated soil or through accidental oral ingestion. Remember, the next time you’re outside, wipe the sweat from your face with a dirty hand and then lick your lips or have a drink – it’s that simple. After hose or rainwater washes contaminated poop into the soil, these parasite eggs can survive and infect for months or years to come.
Once inside the human body, both hookworm and roundworm larvae can mature and migrate through the bloodstream to the lungs. From there, coughing helps them gain access to their host’s digestive tract, where they leach nutrients by adhering to the intestinal wall.
People with healthy immune systems may not show clinical signs of infection, but in sufficient quantities these parasites can lead to anemia and malnutrition. They can even cause intestinal obstruction that may require surgical intervention, especially in young children.
In addition, larval stages of roundworms can enter the human eye and in rare cases lead to permanent blindness. Hookworms can cause a severely itchy condition called cutaneous larva migrans, as the larval worm moves just under the skin of its host.
Once the parasite’s life cycle is complete, it can leave the host’s body as an intact adult worm, which looks like a small piece of cooked spaghetti.
The impact on other animals
Dogs and cats can also develop the same symptoms as humans due to parasitic infections. In addition to risks from hookworms and roundworms, pets are also vulnerable to whipworms, giardia and coccidia.
In addition to parasites, unattended poop can also be contaminated with dog or cat viruses, such as parvovirus, distemper virus and canine coronavirus, which can cause life-threatening illnesses in other dogs and cats, especially in adults that have not been vaccinated and in puppies and kittens.
These viruses attack rapidly dividing cells, especially the intestinal lining and bone marrow, preventing them from properly absorbing nutrients and producing replacement red and white blood cells that help defend against these and other viruses. Vaccination can protect pets.
Many species of local wildlife belong to the family groups of canids and cats. They too are susceptible to many of the same parasites and viruses as dogs and cats, although they are much less likely to have had the benefit of vaccinations. Coyotes, wolves, foxes, raccoons, minks and bobcats are at risk of contracting parvovirus, coronavirus and distemper.
Responsible management of pet waste
So wherever your dog or cat does its business – in the park, in the woods, on the sidewalk or even in your garden – pick up the poop, but always avoid contact with your skin.
It’s safest to use a scoop to transfer the poop directly into a plastic bag, or put a baggie over your hand to pick up the poop and then pull the plastic bag over it. While it’s tempting to skip the “soft” or watery poop, these are often the most likely culprits for spreading disease.
Tie the bag and place it in a garbage can (not on top) to prevent accidental contamination of a neighbor or sanitation worker. Wash your hands immediately, especially before touching your face or eating or drinking. Hand sanitizers can get rid of many viruses on your skin, but they won’t kill parasite eggs.
Other potential sources of poop (and parasite) exposure include sandboxes, beaches, and park sand under and around playgrounds. Sand is comfortable to lounge on, fun to build castles from, and softens the impact if you fall from a play structure. But cats and other small mammals like to use it as a litter box because it is easy to dig and absorbs moisture.
Covering sandboxes when not in use and closely monitoring your surroundings at the beach and playground are important steps to minimize the risks of exposure for everyone.
By keeping your pets adhering to regular parasite prevention protocols, through annual testing for intestinal parasites and routine removal of fecal material from the environment, you can help reduce the risk of these diseases in all mammals in your environment – humans, pets and wildlife – to be kept to a minimum.
Key points to remember to avoid parasites and minimize the impact on your ecosystem:
- Pick up waste and dispose of it safely wherever your pet poops. Then disinfect your hands.
- Wash your hands before eating or touching your face while gardening or working in the yard.
- Avoid flushing poop into the soil. Using rain or a garden hose only removes the visible mess, not the microscopic problems.
- Make sure sandboxes are covered when not in use.
- Keep your pets on monthly deworming schedules for intestinal parasites.
- Have your vet test your pet’s poop annually for intestinal parasites.
Julia Wuerz, Clinical Assistant Professor of Small Animal Clinical Sciences, University of Florida
This article is republished from The Conversation under a Creative Commons license. Read the original article.