Pinworms
(Pinworm Infection in Children and Adults, Enterobiasis)

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Medical Author:

Charles Patrick Davis, MD, PhD

Charles Patrick Davis, MD, PhD

Dr. Charles "Pat" Davis, MD, PhD, is a board certified Emergency Medicine doctor who currently practices as a consultant and staff member for hospitals. He has a PhD in Microbiology (UT at Austin), and the MD (Univ. Texas Medical Branch, Galveston). He is a Clinical Professor (retired) in the Division of Emergency Medicine, UT Health Science Center at San Antonio, and has been the Chief of Emergency Medicine at UT Medical Branch and at UTHSCSA with over 250 publications.

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Medical Editor:

Melissa Conrad Stöppler, MD

Melissa Conrad Stöppler, MD

Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

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Medical Editor:

Jay W. Marks, MD

Jay W. Marks, MD

Jay W. Marks, MD, is a board-certified internist and gastroenterologist. He graduated from Yale University School of Medicine and trained in internal medicine and gastroenterology at UCLA/Cedars-Sinai Medical Center in Los Angeles.

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Pinworm infection is an infection of the large intestine and anal area by a small, white parasite that resembles a "worm." The medical name for the parasite is Enterobius vermicularis, but it is commonly termed a pinworm in both the lay and medical literature. These parasites are also termed seatworms or threadworms, and the infections is medically termed enterobiasis or helminthiasis. Pinworms and other parasitic worms (as a group are termed helminths) feed off of the host animal by adsorbing nutrients from the host animal. Pinworm infections are the most common helminth infection that occurs in the US. The US Centers for Disease Control and Prevention (CDC) estimates about 40 million people are infected with pinworms currently in the US.

Pinworm is the most common worm infection in the United States, and the majority of pinworm infections worldwide occur in temperate climates.

School-age children have the highest rates of pinworm infection. They are followed by preschoolers. Institutional settings including day care facilities often harbor cases of pinworm infection. Sometimes, nearly half of the children may be infected.

Pinworm infection often occurs in more than one family member. Adults are less likely to have pinworm infection, except for mothers of infected children. However, adult sexual partners can transfer the eggs to each other.