What does a positive HSV 1 (Herpes Simplex Virus 1) IgG (Immunoglobulin G) and negative HSV 2 (Herpes Simplex Virus 2) IgG result indicate?

Interpretation of HSV 1/2 IgG Serology Results

Your HSV serology results indicate past infection with HSV-1 (oral herpes) but no evidence of HSV-2 (genital herpes) infection. This pattern is common and generally suggests previous exposure to the oral form of herpes simplex virus.

Understanding Your Results

• HSV-1 IgG: >58.00 (Positive) - This strongly positive result indicates you have been infected with HSV-1 at some point in your life 1
• HSV-2 IgG: <0.90 (Negative) - This result indicates no evidence of HSV-2 infection 1

Clinical Significance

HSV-1 Positive Result

• HSV-1 traditionally causes oral herpes (cold sores) but can also cause genital herpes through oral-genital contact 1
• Most HSV-1 infections are acquired during childhood through non-sexual contact 1
• A high index value (>58.00) indicates established infection and strong antibody response 1
• This is an extremely common infection - up to 70% of adults worldwide have HSV-1 antibodies 1

HSV-2 Negative Result

• The negative HSV-2 result (<0.90) indicates you have not been infected with HSV-2 1
• This result is reliable as HSV-2 serologic tests have high sensitivity (approximately 92%) 1
• False negatives are possible but uncommon with established infections 2

Important Considerations

• HSV-1 can cause genital herpes, so a positive HSV-1/negative HSV-2 result does not rule out genital herpes 1
• If you've had recent exposure (within 12 weeks), the HSV-2 test could potentially be falsely negative due to the window period 1
• Type-specific HSV serologic tests have limitations - HSV-1 tests lack sensitivity (may miss 30% of infections) while HSV-2 tests sometimes lack specificity 1, 2
• If you have recurrent genital lesions despite negative HSV-2 serology, direct testing of lesions by PCR would be more definitive 1, 3

Clinical Implications

• If you have no symptoms, no specific treatment is needed for HSV-1 seropositivity 1
• If you have oral herpes symptoms (cold sores), episodic or suppressive antiviral therapy may be considered 1
• The negative HSV-2 result suggests lower risk for transmitting genital herpes to partners 1
• If concerned about recent exposure to HSV-2, retesting should not occur until at least 12 weeks after exposure 1

Reliability of Results

• Your HSV-1 result is strongly positive (>58.00), making false positivity extremely unlikely 1
• HSV-2 antibody tests are generally reliable for excluding infection when negative 1
• However, up to 12% of patients with recurrent HSV-1 genital lesions may have false-negative serology 2

Remember that these results reflect past exposure and immune response, not necessarily current active infection or symptoms 1.