Key points
- Toxocariasis usually spreads through contact with infected dog or cat feces (poop).
- Once inside the body, eggs hatch and the parasite spreads.
- The best way to prevent toxocariasis is to treat dogs and cats for roundworm and wash your hands after handling pet waste.
Overview
People become infected with toxocariasis when they accidentally consume dirt or food contaminated with roundworm eggs. The eggs get into the soil through animal waste, typically from dogs and cats.
The most common type of Toxocara parasite that infects humans is known as Toxocara canis. Puppies usually get infected with this parasite from their mother before birth or when nursing. When the pup is 3 – 4 weeks old, the roundworms begin to lay eggs inside the puppy. The eggs then get into the soil or environment when the puppy poops.
It takes 2 – 4 weeks in the environment for the eggs to develop enough to cause infection. However, the eggs have a strong protective layer that allows them to survive for months, or even years, under the right conditions. Once inside a person, the eggs hatch and the parasites spread in the body.
Toxocariasis doesn't spread person-to-person like a cold or flu. In rare cases, people may get infected if they eat undercooked or raw meat from animals like lamb or rabbit.
Prevention
There are several ways to prevent toxocariasis, especially if you have a dog or cat.
- Have a veterinarian treat any dogs and cats in your home for worms, especially when they are young and if they spend time outdoors. That will make it less likely that people will encounter parasite eggs.
- Wash your hands with soap and water after playing with your pets or other animals, especially after outdoor activities, and before handling food or eating.
- Keep your pet's living area clean. Pet waste should be picked up daily and buried or bagged and disposed of in the trash. Wash your hands after handling pet waste.
- Teach children that it is dangerous to eat dirt or soil.
- Always cook meat thoroughly before eating.