Herpes simplex virus 1 & 2 – Serology

Consistent with O. Reg. 671/92 of the French Language Services Act, laboratory testing information on this page is only available in English because it is scientific or technical in nature and is for use only by qualified health care providers and not by members of the public.

This page provides serological testing information for Herpes simplex virus (HSV) at Public Health Ontario (PHO). For information regarding other testing options, refer to the following PHO webpages:

Testing Indications

Serologic testing is indicated for determining evidence of past infection with HSV and is not indicated for the diagnosis of acute/recent HSV infection where virus detection from active lesions is the test of choice. If infection or recent exposure is suspected, it is preferable to submit specimens for virus detection, see Herpes Simplex – conjunctivalCSF or Herpes Simplex – Skin and Genital.

HSV-2 Type Specific IgG assay is indicated for testing sexually active adults or expectant mothers to aid in determining evidence of prior infection with HSV-2 virus.  It should not be used to diagnose an episode of suspected genital herpes infection.

Following infection with HSV, it may take up to 3 to 6 months for HSV IgG antibodies to be detectable in serum/blood.

Acceptance/Rejection Criteria

Donor testing is not available through PHO’s laboratory. Specimens from patients being screened as potential donors (e.g. organ, tissue, cells, fertility, etc.) should be referred to a laboratory that performs donor screening assays. Specimens received for donor screening at PHO’s laboratory will be rejected.

Specimen Collection and Handling

Specimen Requirements

Test Requested Required Requisition(s) Specimen Type Minimum Volume Collection Kit

Herpes Simplex 1 & 2 (Type Specific IgG)

Whole blood or serum

5.0 ml (blood) or 1.0 ml (serum)

Blood, clotted – serum separator tubes (SST)

Submission and Collection Notes

1

Complete all fields of the requisition form, including:

  1. Test(s) requests and indications for testing
  2. Patient setting
  3. Specimen type
2

Label the specimen container(s) with the patient’s first and last name, date of collection, and one other unique identifier such as the patient’s date of birth or Health Card Number. For additional information see: Criteria for Acceptance of Patient Specimens. Failure to provide this information may result in rejection or testing delay.

3

HSV type specific IgG (HSV-1 and HSV-2) testing will be performed on all request for HSV serology.

Limitations

Haemolyzed, icteric, lipemic or microbially contaminated sera are not recommended for testing.

Storage and Transport

Centrifuge if using SST. Place specimen in biohazard bag and seal. Specimens should be stored at 2-8°C following collection and shipped to PHOL on ice packs.

All clinical specimens must be shipped in accordance to the Transportation of Dangerous Goods Act.

Requisitions and Kit Ordering

Test Frequency and Turnaround Time (TAT)

HSV-1 & HSV-2 IgG serology is performed daily Monday to Saturday.

Turnaround time for test results is up to 5 business days from receipt at PHO’s laboratory.

Test Methods

The DiaSorin LIAISON® HSV-1 and HSV-2 Type Specific IgG assay is a chemiluminescent immunoassay (CLIA) technology used for the qualitative determination of specific IgG antibodies to Herpes simplex virus Type 1 (HSV-1) and Type 2 (HSV-2) in human serum. The test is performed on the LIAISON® XL Analyzer.

The LIAISON® HSV-2 Type Specific IgG assay has not been established for use in the pediatrics population, for neonatal screening, or for testing immunocompromised or immunosuppressed patients. The assay is neither FDA cleared nor approved for testing blood or plasma donors.

Interpretation

The presence of HSV IgG antibodies (in asymptomatic persons) provides an indicator of past infection with either HSV Type 1 or Type 2 or both.

IgG antibody levels may be reported as Non-Reactive (no detectable antibody), Indeterminate (the level of antibody detected is considered borderline reactive or equivocal) or Reactive (antibody is detectable within the positive range of the assay).

Please be aware that a non-reactive IgG level does not always indicate the absence of current infection. It may take up to 3 to 6 months for HSV IgG to develop after exposure especially if a patient has been treated with antiviral medication.

In symptomatic patients indeterminate levels of antibody may indicate rising antibody levels following acute infection. In asymptomatic patients indeterminate levels of antibody may be due to genuinely low levels of IgG antibody many years after the initial infection.

HSV-1 IgG Test Result

HSV-2 IgG Test Result

Interpretations

Non-Reactive

Non-Reactive

Herpes simplex Virus type 1 IgG and Herpes simplex Virus type 2 IgG antibodies not detected.

Non-Reactive

Reactive

Herpes simplex Virus type 1 IgG antibodies not detected; Herpes simplex Virus type 2 IgG antibodies detected.

Reactive

Non-Reactive

Herpes simplex Virus type 1 IgG antibodies detected; Herpes simplex Virus type 2 IgG antibodies not detected.

Reactive

Reactive

Herpes simplex Virus type 1 IgG and Herpes simplex Virus type 2 IgG antibodies detected.

Reporting

Results are reported to the physician, authorized health care provider (General O. Reg 45/22, s.18) or submitter as indicated on the requisition.

contact lab

Contact Laboratory Customer Service

Laboratory Services

customerservicecentre@oahpp.ca

Updated 13 June 2023