A stool ova and parasites exam involves a laboratory analysis of a stool sample to check for parasites. Parasites are organisms that can live inside a host (the human body) and cause infections in the intestines.
Your doctor may order this exam if you have symptoms that point to a possible parasitic infection. Usually, these symptoms include stomach pain, diarrhea, nausea, and blood or mucus in your stool. Fever and headache can also accompany the abdominal symptoms.
The test also may be ordered if you recently drank untreated water or visited a developing country where you may have been exposed to a parasitic infection. Children should probably be tested if other children at their schools or daycare centers have been ill with parasites.
A stool sample test causes no discomfort. Your doctor will provide you with a kit containing plastic wrap to loosely place over the toilet. This should be held in place by the toilet seat. A special toilet tissue is also provided. You will use this to put the sample in a sterile container. If the sample is being collected from a child in diapers, the diaper can be lined with the plastic wrap.
Once you have collected your stool sample, you need to drop it off at your doctor’s office or a laboratory. The lab will analyze the sample under a microscope, looking for parasites. The laboratory will then give the results to your doctor, who will share them with you.
There are no risks involved with testing.
In general, you do not need to do anything to prepare for this test. In some cases, your doctor may request that you stop taking certain medications for up to two weeks before the test, since they can alter the results. These might include antacids, anti-diarrhea drugs, laxatives, antibiotics and anti-parasitic medicines.
You should also tell your doctor about any other medications you take, and whether you recently had any imaging tests that used contrast or dye. The dye also may interfere with the parasite exam results.
Normal results means there was no parasites or parasite eggs found in the stool sample. In this case, a parasite infection is an unlikely cause of your symptoms.
An abnormal result means parasites or eggs have been found in the stool sample—you have a parasitic infestation. There are over 100 different known parasites in the world. Some infections include:
- giardiasis: an infection contracted by drinking water from lakes and streams where animals—like beavers and muskrats—contaminate the water
- amebiasis: an infection spread through contaminated food and water, mostly seen in tropical areas with poor sanitation such as Africa, Mexico, and South America
- strongyloidiasis: an infection spread through contact with soil that contains roundworms, mostly found in warm, moist areas
- taeniasis: a type of tapeworm infection that is caused by eating infected meat, such as beef
There are many different medications available to treat the parasites that cause infections. Your doctor will prescribe the right medication for the type of parasite you have. Talk with your doctor about alternative treatments if you’re interested.