Parasitic Infections

What is giardiasis (giardia)?

A Answers (2)

  • AHealthwise answered
    Giardiasis (also called giardia) is an illness caused by infection with the parasite Giardia lamblia, also known as Giardia intestinalis. Giardiasis is usually caused by drinking water that is contaminated with the parasite. In the United States, G. lamblia is most often found in untreated streams, rivers and lakes. Symptoms of giardiasis include diarrhea, a lot of gas (flatulence), abdominal cramps and nausea. In some people, giardiasis does not cause any symptoms. In other people, the symptoms may keep coming back (recurring). Infection with the parasite can be prevented by hand-washing and by treating water taken from rivers, lakes or streams before drinking it or using it to cook, wash dishes or brush teeth. Symptoms of giardiasis may go away on their own. But medicine, usually metronidazole, can relieve the discomfort and prevent the spread of the illness.

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  • ARealAge answered

    Drinking untreated water -- from a well, stream, or contaminated water system -- can cause diarrhea that may develop within just a few days or up to as much as four weeks after ingestion. It's not the water that's the problem, but the parasites that live in it.

    One of the most common parasites found in untreated water is Giardia lamblia, often simply called giardia (gee-ARE-dee-ah). Outdoor enthusiasts often pick up the parasite from drinking stream or lake water during camping or hiking trips.

    How can you tell if you're infected with giardia? Your doctor will need to test a sample of your stool. If the results are positive, you may be given an antiparasitic drug (a type of antibiotic), such as tinidazole, metronidazole, nitazoxanide, or paromomycin.

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What is giardiasis (giardia)?