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 10/8/2018
Updated by: Linda J. Vorvick, MD, Clinical Associate Professor, Department of Family Medicine, UW Medicine, School of Medicine, University of Washington, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.