Pronounced: gee-ar-dye-a-sis
Giardiasis is a gastrointestinal infection. It is one of the most common parasitic diseases in the world. It may be responsible for for up to a billion cases annually worldwide.
Giardiasis is caused by a tiny parasite called Giardia lamblia . Giardia cysts are a resistant form of the parasite that can survive outside a human or animal body. These cysts cause the spread of this disease. For infection to occur, a person must ingest Giardia cysts by mouth. Once cysts are ingested, the parasites start growing and multiplying in the small intestine. Ingesting as few as ten parasitic cysts can cause an infection.
Giardiasis can be contracted by:
A risk factor is something that increases your chance of getting a disease or condition.
Symptoms usually start 5 to 28 days after infection. Not all people who are infected have symptoms. But, all people who are infected can transmit the disease.
Symptoms may include:
The doctor will ask about your symptoms and medical history, and perform a physical exam. Tests may include:
If you are diagnosed with giardiasis, everyone living in your household should be tested for infection as well.
Giardiasis is treated with a prescription antiparasitic drug. The medication is usually given for 5 to 10 days and may be one of the following:
This condition may be resistant to any of these medications or to several others occasionally used. Resistance may complicate treatment and prolong illness.
To prevent getting or spreading giardiasis:
RESOURCES:
The American Academy of Family Physicians
http://www.familydoctor.org
Maryland Department of Health and Mental Hygiene
http://www.dhmh.state.md.us
Massachusetts Department of Public Health
http://www.state.ma.us/dph/cdc
CANADIAN RESOURCES:
The Canadian Association of Gastroenterology (CAG)
http://www.cag-acg.org/default.aspx
Public Health Agency of Canada
http://www.phac-aspc.gc.ca
References:
Adam RD. Biology of Giardia lamblia . Clin Microbiol Rev. 2001;14:447
American Academy of Family Physicians website. Available at: http://www.familydoctor.org .
Harrison's Principles of Internal Medicine . 15th ed. McGraw-Hill Professional Publishing; 2001.
Massachusetts Department of Public Health. Bureau of Communicable Disease Control website. Available at: http://www.state.ma.us/dph/cdc .
The Merck Manual of Medical Information . Simon and Schuster, Inc; 2000.
Nash TE. Surface antigenic variation in Giardia lamblia . Mol Microbiol. 2002;45:585.
Last reviewed November 2008 by Daus Mahnke, MD
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.
Copyright © 2007 EBSCO Publishing All rights reserved.