Giardiasis
Giardiasis
What is giardiasis?
Giardiasis is an illness caused by Giardia lamblia, a one-celled, microscopic parasite that lives in the intestines of people and animals. During the past 15 years, Giardia lamblia has become recognized as one of the most common causes of waterborne disease in humans in the United States. This parasite is found in every region of the United States and throughout the world.
What are the symptoms of giardiasis?
Diarrhea, abdominal cramps, and nausea are the most common symptoms of giardiasis. These symptoms may lead to weight loss and dehydration. However, not everyone infected has symptoms.
How long after being infected do symptoms appear?
Symptoms usually appear 1-2 weeks after infection with the parasite.
How long will I have symptoms?
In otherwise healthy persons, symptoms may last 4-6 weeks. Occasionally, symptoms last longer.
How can I get giardiasis?
* By putting anything into your mouth that has touched the stool of a person or animal with giardiasis.
* By swallowing water contaminated with Giardia. A person can swallow a Giardia cyst, the infectious stage of the parasite, by consuming water from swimming pools, lakes, rivers, springs, ponds, or streams contaminated with sewage or feces from humans or animals.
* By eating uncooked food contaminated with Giardia cysts. Thoroughly wash with safe water all vegetables and fruits you plan to eat raw.
* By touching and bringing to your mouth cysts picked up from surfaces (i.e., toys, bathroom fixtures, changing tables, diaper pails) contaminated with stool from an infected person.
Who is at risk?
Persons at increased risk for giardiasis include child care workers; diaper-aged children who attend day care centers; international travelers; hikers; campers; and others who drink untreated water from contaminated sources. Several community-wide outbreaks of giardiasis have been linked to drinking municipal water contaminated with Giardia.
What should I do if I think I have giardiasis?
See your health care provider who will ask you to submit stool samples to see if you are harboring the parasite. Because Giardia can be difficult to diagnose, your health care provider may ask you to submit several stool specimens over several days.
What is the treatment for giardiasis?
Several prescription drugs are available to treat Giardia.
How can I prevent giardiasis?
- Wash hands with soap and water after using the toilet and before handling food.
- Avoid water or food that may be contaminated.
- Wash and peel all raw vegetables and fruits before eating.
- Avoid drinking water from lakes, rivers, springs, ponds, or streams unless it has been filtered or chemically treated.
- During community-wide outbreaks caused by contaminated drinking water, boil drinking water for 1 minute to kill the Giardia parasite and make the water safe to drink.
- When traveling in countries where the water supply may be unsafe, avoid drinking unboiled tap water and avoid uncooked foods washed with unboiled tap water. Bottled or canned carbonated beverages, seltzers, or pasteurized fruit drinks, and steaming hot coffee and tea are safe to drink. You should check the label on bottled water to make sure it has been properly filtered before drinking.
- If you work in a child care center where you change diapers, be sure to wash your hands thoroughly with plenty of soap and warm water after every diaper change, even if you wear gloves.
- Avoid swimming in pools if you or your child has Giardia. Giardia cysts are fairly chlorine resistant and are passed in the stools of infected people for several weeks after they no longer have symptoms.
This information provided from:
Division of Parasitic Diseases
National Center for Infectious Diseases
Centers for Disease Control and Prevention
CDC Giardiasis (Giardia) Webpage