Mononucleosis Tests

Why It Is Done

The monospot test is done to help diagnose a recent mono infection.

Epstein-Barr virus (EBV) antibody testing is also done to help diagnose mono. The EBV antibody test can help determine whether you have ever been infected with the virus and whether the infection has been recent.

EBV antibody testing is usually done when you have symptoms of infectious mononucleosis and a monospot test result is negative. EBV antibody testing may also be done to check for antibodies to EBV when a person has a disease or uses medicine that causes problems with the immune system.

How To Prepare

No special preparation is required before having this test.

Talk to your doctor about any concerns you have regarding the need for the test, its risks, how it will be done, or what the results will mean. To help you understand the importance of this test, fill out the medical test information form (What is a PDF document?).

How It Is Done

The monospot test is done on a small sample of blood taken from your fingertip or from a vein. The Epstein-Barr antibody test is done on a blood sample taken from your vein.

Blood test from a finger stick

For a fingertip sample, the health professional taking the sample will:

• Clean your hand with soap and warm water or an alcohol swab.
• Massage your hand without touching the puncture site.
• Puncture the skin on the side of your middle or ring finger with a small instrument called a lancet.
• Wipe away the first drop of blood.
• Place a small tube called a capillary tube on the puncture site and collect a small amount of blood.
• Put a gauze pad or cotton ball over the puncture site as the tube is removed.
• Put pressure on the site and then put on a bandage.

Blood test from a vein

The health professional taking a sample of your blood will:

• Wrap an elastic band around your upper arm to stop the flow of blood. This makes the veins below the band larger so it is easier to put a needle into the vein.
• Clean the needle site with alcohol.
• Put the needle into the vein. More than one needle stick may be needed.
• Attach a tube to the needle to fill it with blood.
• Remove the band from your arm when enough blood is collected.
• Put a gauze pad or cotton ball over the needle site as the needle is removed.
• Put pressure on the site and then put on a bandage.

How It Feels

The blood sample is taken from a vein in your arm or from your fingertip. You may feel nothing at all from the needle or lancet, or you may feel a quick sting or pinch. The elastic band that is wrapped around your upper arm when blood is taken from a vein may feel tight.

What Affects the Test

Reasons you may not be able to have the test or why the results may not be helpful include:

• Having an EBV antibody test within the first few weeks of becoming infected with EBV. This may lead to a false-negative result. If the first test does not indicate mono but you still have symptoms, the test may be repeated.
• Other infection or disease, such as cytomegalovirus (CMV), leukemia or lymphoma, rubella, hepatitis, or lupus. Although the symptoms of these infections and diseases are similar to mono, the monospot test usually will be negative.
• Having a weakened immune system.

What To Think About

• Since many people are exposed to Epstein-Barr virus (EBV) during childhood, most adults have EBV antibodies of a type called IgG. The presence of the IgG type of antibody does not necessarily mean that you have had a recent infection with EBV.
• Although some people think that the Epstein-Barr virus (EBV) may be related to myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), experts have found no evidence for this. The monospot test and the EBV antibody test are not used to diagnose or monitor CFS.
• Children, especially those younger than 2 years, are more likely than adults to have a negative monospot test, even when they have mono. This is called a false-negative result.