Microbiology
Summary
Giardia lamblia is a common parasite associated with campers and hikers who drink unfiltered or unpurified water, typically from a stream or river. This water is often contaminated by animal or possibly human feces that contain the cysts of Giardia, making its transmission primarily fecal-oral.
Giardia causes giardiasis, the symptoms of which include bloating, flatulence, and foul-smelling diarrhea. Giardiasis can also result in steatorrhea, fatty diarrhea due to fat malabsorption. After cysts are ingested, they transform into the trophozoite form, which has a distinctive pear-shaped appearance under a microscope. When identified in stool through an ova and parasites (O and P) test or an enzyme-linked immunosorbent assay (ELISA) stool antigen test, a giardiasis diagnosis is confirmed. The preferred treatment for giardiasis is metronidazole.
Lesson Outline
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FAQs
Giardia lamblia, also known as Giardia intestinalis, is a microscopic parasite that can cause diarrheal illness. It's transmitted through the fecal-oral route, typically when an individual ingests Giardia cysts through contaminated food, water, or via direct contact with an infected person or animal.
People infected with Giardia lamblia may experience symptoms such as diarrhea, excessive gas or flatulence, stomach or abdominal cramps, and bloating. Some people may also experience nausea and weight loss. It should be noted that some infected individuals may remain asymptomatic.
To avoid Giardia and other waterborne pathogens when camping or hiking, do not drink water directly from rivers, streams, springs, or lakes unless it has been purified. This can be done through methods such as boiling, using water filters, or chemical disinfection. It is also recommended to not swallow water while swimming in pools, lakes or rivers.
A Giardia infection is usually diagnosed by testing stool samples. The stool O and P (ova and parasite) test is commonly used to spot the cysts or eggs of the parasite. Another reliable diagnostic tool is the ELISA (enzyme-linked immunosorbent assay) stool antigen test, which can identify proteins or antigens associated with the Giardia parasite.
Most people infected with Giardia lamblia can be treated with prescription drugs that kill the parasite. One of the most commonly used drugs is metronidazole. It's also essential to stay hydrated due to the potential for dehydration caused by diarrhea, one of the main symptoms of the infection.
