Some people love the feel of the garden dirt in their hands as they weed or work the soil. Do you always know what’s in the soil, or who’s been there before you? Pets and wild animals often find garden soil a perfect ‘litter pan’ and will deposit their ‘leftovers’, sometimes burying them well so the evidence is not always clear. This animal fecal matter can contain all sorts of potential pathogens, but the most serious of which are the internal parasites some of these animals might be infected with. Though not all are zoonotic (contagious to people) some are and some are potentially very dangerous. The following article is a discussion of some of these potential problems one might encounter in their garden soils.

As a veterinarian I am often reminding pet owners to wash their hands after cleaning the litter box or handling their pet’s droppings. We routinely deworm for a number of parasites that are common among pets, some of which are very important zoonotic creatures. Round worms, hookworms, tapeworms and a variety of protozoan parasites can be present in your pet’s stools and some of these are problems if you happen to ingest them yourself. And wildlife such as skunks and raccoons can add their own mix of possible parasite zoonoses to the garden soils. Most of the time my comments to clients are directed at their children, as most adults are a bit more cautious and aware of animal fecal matter and much more likely to clean up after handling it. But children can end up playing in sand boxes or garden soil that was previous used by their cat, a neighbor’s cat, the dog, or some other animal that was visiting the garden overnight. And some adults like to garden without gloves in areas of the garden these animals might have frequented.

Round worms, or Ascarids, are very common parasites in dogs, cats and some wild life. These parasites, as is true with all those discussed in this article, have a direct life cycle, meaning all one has to do is eat the eggs laid by the worm and the next host will get the infection (no intermediate host needed as is the case with some parasites). We routinely deworm all cats and dogs in my practice for this parasite as it is ubiquitous, particularly in nursing mothers and their puppies.Roundworms are not difficult to get rid of in a dog or cat, but their eggs are quite durable and can survive in the environment for a long time (years). All a dog or cat need do is ingest some stool or contaminated dirt (or lick off their paws after stepping in some stool) and they get the infection.Round worms travel about their bodies, hiding in lung or liver tissue, and then moving to the intestines to lay eggs and make more worms. This traveling through tissues in the proper host causes very little problems as the round worms have evolved to live relatively ‘peacefully’ in the proper hosts. Human incidental ingestion of these eggs (from not washing hands properly, for example) can lead to something called visceral larval migrans. This is when the little larvae find themselves in the wrong host (us) and ‘get lost’. They can end up just about anywhere (liver, lungs, eyes or brain) and cause problems wherever they go. If they end up in the eye or brain, they can cause severe neurologic problems that can be very difficult to treat, and often cause permanent damage (blindness, brain damage etc.). Raccoon and skunk roundworms are just as bad if even not more dangerous, and these can do the same sorts of damage to our own pets as they do to us, as your dog, cat or rabbit are the incorrect hosts for those species (a good reason to try to keep raccoons and skunks out of your yard). So wash your hands well if you garden barehanded!