What are zoonotic parasites?
Dogs and cats can carry a variety of internal parasites, some of which can cause serious health problems for your pet, and even for your family. Many different types of parasites are ‘zoonotic,’ which means that they can be passed from animals to people.
 
What problems can these parasites cause?
With some types of parasites, including tapeworms and protozoa (primarily coccidian and giardia), the person only experiences relatively mild consequences, such as diarrhea or intestinal problems. Other parasites can cause blindness or even brain damage. The canine roundworm is present in virtually all puppies and at low levels in many adult dogs, and is transmitted by ingestion of feces containing roundworm eggs. When ingested by an abnormal host (often a child), the larvae of this worm migrate south through the body, frequently ending up in the eye, where it causes permanent blindness. The feline roundworm may be a possible cause of this syndrome as well. Raccoon roundworm larvae migrate through the body of abnormal hosts, similarly to canine roundworms, but frequently locate in the brain of people or other animals, causing brain damage or death. Hookworm larvae migrate through the skin, causing a rash or itchiness. Exposure to this parasite most commonly occurs by walking barefoot outside. The hydatid tapeworm, which is sometimes seen in dogs that have eaten sheep of wild ruminants (such as deer, etc), causes hydatid cyst disease in people, and can even be fatal.

How do I know if my pet has parasites?
Although many people think that parasite test and deworming are only necessary for young animals and those with diarrhea or visible worms in the stool, this isn’t the case. Puppies and kittens are more likely than adults to have high parasite loads, but the vast majority of internal parasites can only be diagnosed by looking at a fecal sample under the microscope. It is the exception, not the rule, to see visible worms. Many pets may not even show symptoms of infestation.

How can I keep my pet and my family safe?
The risk of zoonatic parasite transmission can be minimized or prevented by strategic deworming of your pet, consistent feces removal from your yard and litter boxes, and using good hygiene and teaching it to your children. Flea prevention is also an important factor in the prevention of one type of tapeworm. All puppies and kittens should be dewormed at least three to four times. Adult dogs and cats should have a parasite test (fecal floatation) done at least once a year, and be treated appropriately for any parasites found. This is especially important for dogs and cats that hunt or eat wild animals, or those on raw food diets. It is important to do the fecal floatation instead of merely deworming because different types of parasites require different medications for treatment. Feces should be removed at least twice weekly from the yard, and daily from the litterbox. Make sure cats and raccoons do not have access to your child’s sandbox. Use gloves when gardening. Wash your hands and your child’s after handling your pet, and do not let pets (especially puppies) lick your mouth.