Did you know that 10,000 humans are infected annually by pet roundworms, according to the Centers for Disease Control and Prevention? A recent study conducted by Braun Research found that 83 percent of dog owners are unaware their pets' waste can cause a parasite infection in humans.

These internal parasites are spread through exposure to infective organisms in a fecally contaminated area and can exist in many places, including public sandboxes, public parks, and even your own backyard.

Internal parasites, like roundworms and hookworms, can be passed from animals to people — the definition of a zoonotic disease.

People may contract the larvae or eggs of these parasites through direct contact with infected feces or contaminated soil, sand, plant life and other objects. Eggs or larvae of either type may be ingested accidentally (they're so small you can't see them), but hookworm larvae usually enter the body by penetrating the skin.

Researchers believe children are more vulnerable to infection than adults because children's play habits bring them into closer contact with contaminated objects and also because they're more likely to put contaminated objects into their mouths. The elderly and immuno-compromised populations are also at increased risk.

To minimize the risk to both pets and people follow these steps: