Giardiasis

[exinilu]

Giardiasis is an infection of the small intestine caused by the single-celled protozoan parasite Giardia. The main symptoms are abdominal cramping and diarrhea.

People may have abdominal cramping, gas, belching, diarrhea, and nausea and feel tired.
People acquire the infection by drinking water or eating food that is contaminated with stool containing Giardia or by coming into contact with stool from an infected person.
Doctors diagnose the infection by testing or examining a stool sample.
Boiling water kills Giardia protozoa and is the safest way for hikers to ensure that water from streams and lakes is safe to drink.
Infected people are treated with an antiparasitic drug, such as tinidazole , metronidazole , or nitazoxanide .

(See also Overview of Parasitic Infections.)
Giardiasis is a protozoan infection that occurs worldwide and is the most common parasitic infection of the intestine in the United States. Giardia protozoa can form an outer shell (called a cyst). It enables them to survive outside the body for long periods of time (for example, in lakes and streams) and makes them less likely to be killed by chlorine (for example, in swimming pools). These cysts are passed in stool and can cause infection.
Giardia protozoa are a common contaminant of fresh water, including many lakes and streams—even ones that appear clean. Poorly filtered municipal water supply systems contribute to some outbreaks. Most people acquire the infection from drinking contaminated water. But people can acquire the infection if they eat contaminated food or have contact with stool from an infected person, which can occur between children or sex partners.
Giardiasis is more common among

Children in day care centers
People who practice oral-anal sex
People who have traveled to developing countries
Backpackers and hikers who drink untreated water from streams and lakes
People who swim in contaminated pools or lakes

Giardia can live in wild animals.

[Sommer]

Infection of the intestine with a flagellate protozoan, which causes diarrhea and other symptoms.