Patient education: Ova and parasite test (The Basics)

What are ova and parasites? — 

"Ova" means eggs. "Parasites" are tiny germs that can cause infection if they get into the body. This can happen in different ways, for example, through food or water.

An ova and parasite test checks stool (bowel movements) for certain parasites or their eggs. This is done by sending a stool sample to a lab, where the staff looks at it under a microscope. The results can show if you have an infection.

This test is sometimes called an "O&P."

Why might I get an ova and parasite test? — 

Your doctor might order this test if you have symptoms of a parasitic infection. Symptoms might include:

●Persistent diarrhea, particularly in people with a weak immune system

●Travel to certain areas where parasites are more common

●If there is an outbreak of infection from the water supply

How do I prepare for an ova and parasite test? — 

You should not need to do anything special to prepare.

Your doctor will give you a special kit or containers to collect stool samples at home.

How do I collect a stool sample? — 

Your doctor will give you specific instructions. It's important to read these carefully.

In general, these are the steps:

●Prepare your supplies or container when you are ready to have a bowel movement.

●Follow the instructions to get a small sample of your stool. You might need to put plastic wrap over the toilet to catch the stool, or the stool might go directly into the container. Try to avoid getting urine in the sample.

●Wash your hands after collecting the sample.

●You will probably need to collect several stool samples over a few days. Follow the instructions for how to store the samples.

●Follow your doctor's instructions for returning your samples.

If you need to collect a stool sample from someone who wears diapers, you will get instructions on how to do this. It usually involves putting a piece of plastic wrap inside the diaper to catch a sample.

What do my results mean? — 

Your doctor or nurse will tell you when to expect your results, and will contact you with the results. Or if you use an online "patient portal," you might get an alert there when your results are ready.

The results can be:

●Negative – This means the test did not find ova or parasites in the sample.

●Positive – This means the test did find ova, parasites, or both in the sample. Your doctor or nurse will talk to you about what to do next.

If you do have an infection, your doctor will work with you to come up with a treatment plan.

More on this topic

Patient education: Stool collection for testing (The Basics)
Patient education: Giardia (The Basics)
Patient education: Cryptosporidiosis (The Basics)
Patient education: Diarrhea in teens and adults (The Basics)
Patient education: Diarrhea in children (The Basics)
Patient education: Food poisoning (The Basics)

Patient education: Giardia (Beyond the Basics)
Patient education: Acute diarrhea in adults (Beyond the Basics)
Patient education: Acute diarrhea in children (Beyond the Basics)
Patient education: Foodborne illness (food poisoning) (Beyond the Basics)