Pinworms are small white worms that live in the rectum (the very last section of the large intestine). The human pinworm is called Enterobius vermicularis. Pinworm infections tend to be fairly mild (the sight of them is often more distressing than what they actually do), causing itching around the anus. Pinworms are common in young children and can be spread between people living in the same household. Pinworms are transmitted by swallowing pinworm eggs, which can survive in the environment for up to 2 weeks. Handwashing after using the bathroom is a key way to reduce the risk of transmission.
A recurring myth is that pets are a source of pinworm infections in people. Pets cannot spread human pinworms, nor can they become infected by human pinworms.
If your child has pinworms, there are various measures that should be taken to reduce transmission and prevent recurrence. But testing, treating or banishing the household pet is not one of them!