Question 2. Does a negative result mean that the patient has not been exposed to HSV?

Not necessarily. A negative result does not rule out infection, because the specimen may have been collected before antibodies reached detectable levels.2 This assay can detect HSV IgG antibodies as early as 3 weeks after the onset of symptoms.2 However, people seroconvert at different rates, and some do not seroconvert for 6 months or longer.2 Additionally, a very small percentage (0.2%) of HSV-2 isolates lack glycoprotein G (gG).3 When the infecting HSV isolate is gG deficient, a false-negative result may occur.

Herpes Simplex Virus (HSV) Type-Specific IgG Antibodies

Test code(s) 6447, 3636X, 3640

A positive result strongly suggests a recent or past HSV infection. The person may be capable of transmitting the virus to others.

A small percentage of positive HSV-2 IgG results may be false-positive.¹ Further testing may be appropriate for patients with a low or unexpected positive HSV-2 IgG result. The HSV-2 IgG Inhibition, ELISA performed at Quest Diagnostics Infectious Disease can be used to further characterize the sample and distinguish a false-positive from a true-positive result. Contact your local Quest Diagnostics laboratory to order this test.

Not necessarily. A negative result does not rule out infection, because the specimen may have been collected before antibodies reached detectable levels.² This assay can detect HSV IgG antibodies as early as 3 weeks after the onset of symptoms.² However, people seroconvert at different rates, and some do not seroconvert for 6 months or longer.²

Additionally, a very small percentage (0.2%) of HSV-2 isolates lack glycoprotein G (gG).³ When the infecting HSV isolate is gG deficient, a false-negative result may occur.

References

Aurelian, L. Herpes simplex viruses. In: Specter S, and Lanoz GL, eds. Clinical Virology Manual. 2^nd ed. New York: Elsevier; 1992:473-497.
Ashley-Morrow R, Krantz E, Wald A. Time course of seroconversion by HerpeSelect ELISA after acquisition of genital herpes simplex virus type 1 (HSV-1) or HSV-2. Sex Transm Dis. 2003;30:310-314.
Liljeqvist JA, Svennerholm B, Bergström T. Typing of clinical herpes simplex virus type 1 and type 2 isolates with monoclonal antibodies. J Clin Microbiol. 1999;37:2727-2718.

This FAQ is provided for informational purposes only and is not intended as medical advice. A clinician’s test selection and interpretation, diagnosis, and patient management decisions should be based on his/her education, clinical expertise, and assessment of the patient.

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Herpes Simplex Virus (HSV) Type-Specific IgG Antibodies

add Question 1. What does a positive HSV-1 or HSV-2 IgG result mean?

add Question 2. Does a negative result mean that the patient has not been exposed to HSV?