This is the head of a pinworm. Pinworms are most common in children. They are easily transmitted and sometimes appear in small outbreaks among school children.
Review Date: 7/26/2010 Reviewed By: Neil K. Kaneshiro, MD, MHA, Clinical Assistant Professor of Pediatrics, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.