What is giardia infection?

Giardia is the name of a parasite that is scientifically known as Giardia lamblia. This parasite causes a contagious disease, called giardiasis, by infecting the intestinal tract of humans, resulting in nausea, vomiting, diarrhea, and other gastrointestinal symptoms.

Giardia infection is the most common intestinal parasitic disease in the United States. About 2% of adults and 6% to 8% of children in the United States and other developed countries have had giardia infection. In contrast, up to one-third of people in developing countries have been infected (Source: CDC).

Giardia spreads among humans through contaminated food and water. Most commonly, people become infected with giardia from drinking untreated, contaminated water from streams, lakes or ponds. Once a person is infected, the parasite lives in the intestines and is passed in the stool of the infected person. Animals such as cats, dogs and cattle can also be infected and spread the disease to humans. Within industrialized countries, Giardia outbreaks are common in day care centers where the disease is spread by direct contact and substandard hygienic practices.

The signs and symptoms of giardia infection can last for one to two weeks or even longer. The disease course varies among individuals. Some people infected with giardia have no symptoms at all, while others may have severe diarrhea or vomiting that may pose a risk of dehydration. Fortunately, giardia infection can be treated successfully with antibiotics. Even better, you can reduce your risk of giardia infection by following commonsense hygiene practices, such as washing your hands with soap and water prior to preparing food and after handling dirty diapers or using the bathroom.

Left untreated, giardia infection may lead to severe dehydration. Severe dehydration and electrolyte imbalances can result in shock or coma and may be life threatening. Seek prompt medical care if you develop diarrhea and vomiting and believe you may have been exposed to giardia. Seek immediate medical care (call 911) if you, or someone you are with, have symptoms of severe dehydration, such as confusion, lethargy, loss of consciousness, cold skin, or reduced urine production.


What are the symptoms of giardia infection?

Giardia infection causes irritation and inflammation of the intestines that may result in a number of symptoms. The symptoms can vary in intensity among individuals.

Common symptoms of giardia infection

The most common symptoms of giardia infection are related to disturbances of the digestive system and include:


What causes giardia infection?

Giardia infection is caused by the parasite Giardia lamblia. The parasite is present in the stool (feces) of infected people and animals. When water sources are contaminated with feces containing giardia, drinking from these water sources spreads the parasite. For this reason, giardia infection occurs most frequently in people traveling to developing countries or in hikers and campers who have ... Read more about giardia infectioncauses


How is giardia infection treated?

Treatment for giardia infection begins with seeking medical care from your health care provider. To determine if you have giardia, your health care provider will ask you to provide stool samples for laboratory testing.

Antibiotic therapy is the mainstay of treatment for giardia infection and is highly effective. It is important to follow your treatment plan for giardia precisely a... Read more about giardia infectiontreatments

Medical Reviewer: William C. Lloyd III, MD, FACS Last Annual Review Date: Aug 23, 2013 Copyright: © Copyright 2014 Health Grades, Inc. All rights reserved. May not be reproduced or reprinted without permission from Health Grades, Inc. Use of this information is governed by the HealthGrades User Agreement.

This Article is Filed Under: Infections and Contagious Diseases

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