How the Test is Performed

A blood sample is needed. For information on how this is done, see: Venipuncture

The sample is taken to the laboratory and tested for the presence and amount of antibodies.

How to Prepare for the Test

No special preparation is needed for this test.

How the Test Will Feel

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

Why the Test is Performed

The test is done to find out whether a person has ever been infected with oral or genital herpes. It looks for antibodies to herpes simplex virus 1 (HSV-1) and herpes simplex virus 2 (HSV-2). This test does not detect the virus itself.

Normal Results

A negative (normal) test usually means you have not been infected with HSV-1 or HSV-2.

If the infection occurred very recently (within a few weeks to 3 months), the test may be negative, but you may still be infected. This is called a false negative.

Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or test different samples. Talk to your doctor about the meaning of your specific test results.

What Abnormal Results Mean

A positive test means you have been infected with HSV recently or at some point in the past.

Tests can be done to help determine if you have a recent infection.

Approximately 70% of adults have been infected by HSV-1 and have antibodies against the virus. About 20% of adults will have antibodies against the HSV-2 virus, which causes genital herpes.

HSV stays in your system once you have been infected. It may be "asleep" (dormant), and cause no symptoms, or may flare up and cause symptoms. This test cannot tell whether you are having a flare-up.

Risks

Veins and arteries vary in size from one patient to another and from one side of the body to the other. Obtaining a blood sample 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)

Considerations

While HSV-1 and HSV-2 are usually only active from time to time, once they're in your system, they stay there for the rest of your life.

Ask your doctor what steps you need to take if you develop symptoms. Ask how to decrease your risk of spreading the virus to other people. Condoms may not fully protect against HSV.

Alternative Names

Herpes serology; HSV blood test

References

Habif TP. Sexually transmitted viral infections. In: Habif TP, ed. Clinical Dermatology. 5th ed. St. Louis, Mo: Mosby Elsevier; 2009:chap 11.

Workowski KA, Berman S; Centers for Disease Control and Prevention (CDC). Sexually transmitted diseases treatment guidelines, 2010. MMWR Recomm Rep. 2010 Dec 17;59(RR-12):1-110.

Schiffer JT, Corey L. Herpes simplex virus. In: Mandell GL, Bennett JE, Dolin R, eds. Principles and Practice of Infectious Diseases. 7th ed. Philadelphia, Pa: Elsevier Churchill Livingstone; 2009:chap 136.

Updated: 4/12/2012

Reviewed by: Linda J. Vorvick, MD, Medical Director, MEDEX Northwest Division of Physician Assistant Studies, University of Washington, School of Medicine; Susan Storck, MD, FACOG, Chief, Eastside Department of Obstetrics and Gynecology, Group Health Cooperative of Puget Sound, Bellevue, Washington; Clinical Teaching Faculty, Department of Obstetrics and Gynecology, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.