Giardiasis - Overview
Giardia; Traveler's diarrhea - giardiasis
Definition of Giardiasis:
Giardiasis is an infection of the small intestine caused by a microscopic organism (protozoa), Giardia lamblia.
Causes, incidence, and risk factors:
Giardiasis outbreaks can occur in communities in both developed and developing countries where water supplies become contaminated with raw sewage.
It can be contracted by drinking water from lakes or streams where water-dwelling animals such as beavers and muskrats, or domestic animals such as sheep, have caused contamination. It is also spread by direct person-to-person contact, which has caused outbreaks in institutions such as day care centers.
Travelers are at risk for giardiasis throughout the world. Campers and hikers are at risk if they drink untreated water from streams and lakes. Other risk factors include:
- Exposure to a family member with giardiasis
- Institutional (day care or nursing home) exposure
- Unprotected anal sex
- Reviewed last on: 5/25/2010
- Linda J. Vorvick, MD, Medical Director, MEDEX Northwest Division of Physician Assistant Studies, University of Washington, School of Medicine; Jatin M. Vyas, MD, PhD, Assistant Professor in Medicine, Harvard Medical School; Assistant in Medicine, Division of Infectious Disease, Department of Medicine, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.
Hill DR, Nash TE. Giardia lamblia. In: Mandell GL, Bennett JE, Dolin R, eds. Principles and Practice of Infectious Diseases. 7th ed. Philadelphia, Pa: Elsevier Churchill Livingstone; 2009:chap 280.
Huston CD. Intestinal protozoa. In: Feldman M, Friedman LS, Sleisenger MH, eds. Sleisenger & Fordtran's Gastrointestinal and Liver Disease. 8th ed. Philadelphia, Pa: Saunders Elsevier; 2006: chap 106.
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