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Giardia Facts
According to Giardia facts, this is one of the most common intestinal parasites in the world. This one-celled microscopic organism is found in soil, food, water, and contaminated surfaces. Other Giardia facts indicate that this is the most common nonbacterial cause of diarrhea in the United States, especially in children, and transmission only occurs through ingestion of the parasite.
Giardia, which is also commonly known as Giardia intestinalis or Giardia lamblia, is a single-celled microscopic parasite that causes the diarrheal illness giardiasis. After initial infection occurs, Giardia multiplies within the intestines, and symptoms begin developing within one to two weeks.
The following Giardia facts offer statistics on the prevalence of the disease:
- Giardia is the most common nonbacterial cause of diarrhea in the United States
- Giardia is one of the most common intestinal parasites worldwide, infecting up to 20 percent of the world's population
- Giardia is most prevalent in developing countries, where infections are associated with poor sanitary conditions
- Giardia infections are more common in children than in adults
- Chronic Giardia is more common in adults.
The following Giardia facts present information on how the parasite is transmitted:
- Giardia can be found in soil, food, water, and surfaces that have been contaminated with the feces from infected humans or animals
- Giardia transmission can occur by accidentally swallowing the parasite
- A person cannot become infected with Giardia through contact with blood.
The following Giardia facts explain common symptoms of infection:
- Symptoms of Giardia generally occur 1 to 2 weeks after initial transmission
- Common symptoms include: diarrhea, gas or flatulence, abdominal pain, upset stomach, or nausea
- Symptoms may lead to weight loss and dehydration.
Written by/reviewed by: Arthur Schoenstadt, MD
Last reviewed by: Arthur Schoenstadt, MD