Screening for Asymptomatic HSV-2 Infection
Type-specific serological testing using glycoprotein G-based assays is the recommended method for screening asymptomatic individuals for HSV-2 infection. 1, 2
Recommended Testing Approach
- Type-specific serological assays such as enzyme immunoassays (EIAs) that detect antibodies to HSV glycoprotein G-2 (gG-2) should be used for screening asymptomatic individuals for HSV-2 infection 2, 1
- These tests have high sensitivity and specificity (approximately 97% and 98%, respectively) for detecting HSV-2 antibodies 2
- Venous blood samples should be collected for serological testing 2
- Nucleic acid amplification tests (NAATs) are not appropriate for screening asymptomatic individuals without lesions 1
Target Populations for Screening
- Type-specific HSV-2 serology should be used selectively for the following high-risk groups: 2, 1, 3
- Pregnant women at risk of acquiring HSV infection close to delivery
- Men who have sex with men
- People who are HIV positive
- Sexual partners of individuals with known genital herpes
- Widespread screening for HSV-2 antibodies in the general population is discouraged 2, 1, 3
- The US Preventive Services Task Force recommends against routine screening for HSV-2 infection among asymptomatic adolescents and adults 1
Interpretation of Results
- A positive HSV-2 IgG antibody test indicates past exposure and ongoing latent infection with HSV-2 3
- HSV-2 antibodies develop within several weeks after infection and persist indefinitely 3
- The test cannot distinguish between recent and long-standing infections 3
- False positives are more common in individuals with HSV-1 infection, especially with low index values 3
Confirmatory Testing
- For low positive results (index value <3.0), confirmation with a second test using a different glycoprotein G antigen is recommended 3
- Using the Biokit HSV-2 rapid assay as a confirmatory test improves the specificity of tests like HerpeSelect from 93.2% to 98.7% compared to Western blot 3
- Western blot/immunoblot is considered the gold standard for HSV serologic testing but has limited availability 3
Clinical Pitfalls and Considerations
- A negative result within 12 weeks of potential exposure may represent the "window period" and should be repeated after 12 weeks if recent acquisition is suspected 3
- Serological tests alone cannot determine the etiology of a presenting genital lesion with certainty 2
- IgM testing is not recommended for screening as approximately one-third of patients with recurrent genital herpes caused by HSV-2 have IgM responses, making it a poor indicator of recent infection 2
- HSV type determination is important for counseling and prognosis, as HSV-2 has more frequent recurrences and subclinical shedding than HSV-1 in genital infections 1, 3
Post-Test Management
- Patients with positive HSV-2 serology should be counseled about the natural history of the disease, potential for recurrent episodes, asymptomatic viral shedding, and sexual transmission risk 1
- Patients should be advised to abstain from sexual activity while lesions are present, and condom use should be encouraged during all sexual exposures 1
- Treatment options include episodic therapy for outbreaks or suppressive therapy to reduce recurrences and transmission risk 3