Factors that increase the risk of being infected by pinworm include:

• Age. Pinworm infections are most common in children who are 5 to 10 years old.¹
• Household contact. If one child in a home gets a pinworm infection, it is likely that other children in the home will have the infection. Parents are also more likely to get the infection.
• Attending day care centers, schools, and summer camps. Pinworms are easily transmitted and spread among groups of children.
• Living in an institution. Up to 50% of people living in an institution are infected by pinworms.²

Factors that increase the risk of spreading pinworm infections include:

• Living in a warm, moist climate. In warm, moist environments, pinworms are able to live longer outside the body.
• Living in an institution. Pinworms are easily transmitted and spread where people are living in close conditions (such as institutions).
• Poor hygiene practices, especially poor hand-washing. An infected person can spread pinworms to others if he or she does not wash his or her hands well.
• Sharing bedding. Also, fanning the bedding of an infected person can release pinworm eggs into the air.