Epstein-Barr virus test

Definition

Epstein-Barr virus test is a blood test to detect antibodies to the Epstein-Barr virus (EBV) antigens.

See also: Monospot test

Alternative Names

EBV antibody test; Monospot

How the test is performed

Blood is typically drawn from a vein, usually from the inside of the elbow or the back of the hand. The site is cleaned with germ-killing medicine (antiseptic). The health care provider wraps an elastic band around the upper arm to apply pressure to the area and make the vein swell with blood.

Next, the health care provider gently inserts a needle into the vein. The blood collects into an airtight vial or tube attached to the needle. The elastic band is removed from your arm.

Once the blood has been collected, the needle is removed, and the puncture site is covered to stop any bleeding.

In infants or young children, a sharp tool called a lancet may be used to puncture the skin and make it bleed. The blood collects into a small glass tube called a pipette, or onto a slide or test strip. A bandage may be placed over the area if there is any bleeding.

The sample is sent to a lab, where a lab specialist looks for antibodies to the Ebstein-Barr virus. An antibody defends the body against bacteria, viruses, fungus, or other foreign bodies (antigens). Microorganism can stimulate the body to produce these antibodies during active infection. Antibody production increases during the course of infection.

In the first stages of an illness, little antibody may be detected. For this reason, serology tests are often repeated 10 days to 2 weeks or more after the initial sample. In the laboratory, the antibodies react with antigens in specific ways that can be used to confirm the identity of a microorganism.

How to prepare for the test

There is no special preparation for the test.

How the test will feel

When the needle is inserted to draw blood, you may feel moderate pain, or only a prick or stinging sensation. Afterward, there may be some throbbing.

Why the test is performed

The test is done to detect an infection with the Epstein-Barr virus (EBV). The EBV antibody test will detect not only a recent infection but one that occurred in the past. It can be used to tell the difference between a recent or previous infection.

Normal Values

No antibodies to EBV will be detected in the blood of people who have never been infected with EBV.

What abnormal results mean

A positive result means there are antibodies to EBV in the person's blood, ndicating a current or prior infection with EBV.

What the risks are

There is very little risk involved with having your blood taken. Veins and arteries vary in size from one patient to another and from one side of the body to the other. Taking blood from some people may be more difficult than from others.

Other risks associated with having blood drawn are slight but may include:

• Excessive bleeding
• Fainting or feeling light-headed
• Hematoma (blood accumulating under the skin)
• Infection (a slight risk any time the skin is broken)

Special considerations

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References

Schooley RT. Epstein-Barr virus infection. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier. 2007: chap 400.

Warner EA, Herold AH. Interpreting laboratory tests. In: Rakel RE. Textbook of Family Medicine. 7th ed. Philadelphia, Pa: Saunders Elsevier; 2007: chap 66.