 Light infestations (<100 worms) frequently have no symptoms.Heavier infestations, especially in small children, can present gastrointestinal problems including abdominal pain and distension, bloody or mucus-filled diarrhea, and tenesmus (feeling of incomplete defecation, generally accompanied by involuntary straining).Mechanical damage to the intestinal mucosa may occur, as well as toxic or inflammatory damage to the intestines of the host.