What is a stool ova and parasites test?
Your doctor can order a stool ova and parasites (O&P) test to check
for parasites and their eggs in your stool, or feces. It’s a relatively easy
and common test. Your doctor will likely ask you to collect a sample of your
stool at home. Then the sample will be delivered to a laboratory for testing.
If your stool tests positive for parasites or
their eggs, your doctor will prescribe treatment to eliminate the infection.
When is an O&P test ordered?
Your doctor may order an O&P test for a
few reasons. For example, they may order the test if you show signs and
symptoms of an intestinal infection,
- frequent diarrhea
- mucus or blood in your stool
- nausea or vomiting
- severe abdominal pain
In some cases, your doctor might order the
test before you show signs of an infection. For example, if there’s a parasitic
outbreak at your child’s day care or school, they may encourage your child to
be tested. They may also recommend testing if you’ve recently traveled out of
the country in an area where parasites are endemic or you’ve consumed untreated
There are many possible causes of intestinal
symptoms, such as recent use of antibiotics. Along with the O&P test, your
doctor will obtain a detailed history and may also order other laboratory
tests. For example, they may also order a stool culture to check your stool for
How should you prepare for the O&P test?
In most cases, an O&P test doesn’t
require special preparation. In some cases, your doctor may ask you to avoid
using certain products before collecting a sample of your stool. For example,
they may ask you to avoid taking:
- antidiarrheal medications
- contrast dyes, which are used in imaging
studies and X-rays
How is the test conducted?
doctor orders an O&P test, you will need to provide a sample of your stool.
Collect a small sample of your stool using latex gloves or plastic wrap. For
example, consider covering the bowl of your toilet with a loose layer of
plastic wrap before using it. The plastic wrap will catch your stool, making it
easy to collect. Avoid mixing your stool sample with urine or toilet paper.
If you need to collect a sample of stool from
your child, it may require additional steps. You may need to help them,
especially if they’re not quite potty-trained. You can collect a sample of
stool from their diapers, as long as the sample isn’t soiled with urine. In
some cases, your doctor may recommend using a clean cotton swab to collect a
sample of stool from their rectum.
After you’ve collected a sample of stool,
place it in a clean container and seal it. Then take the sealed container to a
clinic or laboratory, as instructed by your doctor. A technician will use dye
and a microscope to look for parasites and eggs in your stool sample.
Your doctor will likely call when the results
are available. They may be available in as little as two days or less.
What do the test results mean?
A “normal” test result means that no eggs or
parasites were found in your stool sample. If you receive a normal result but
your symptoms haven’t subsided, your doctor may order additional tests or
An “abnormal” test result means that
parasites, eggs, or both have been found in your stool sample. Parasitic
infections in the United States are rare but can be caused by:
Your O&P test may also detect:
Based on your test results, your doctor will
recommend treatment or other follow-up steps. For example, they may prescribe
antiparasitic medications. The goal of treatment is to relieve your symptoms
and kill any parasites or other disease-causing organisms in your system.
What are the risks of an O&P test?
Like other tests of its kind, the O&P
test poses no health risks. Collecting a stool sample is an easy procedure that
you can complete at home. If you experience difficulties producing or
collecting a sample, call your doctor.
If you suspect you may have a parasitic
infection, make an appointment with your doctor. It’s best to take the O&P
test as quickly as possible. This can help your doctor treat your infection
before parasitic eggs hatch in your lower intestinal tract.