I have a history of herpes and my recent HSV‑2 IgG (type‑specific) test came back non‑reactive; what does this result indicate?

Your Non-Reactive HSV-2 IgG Result Indicates No Evidence of HSV-2 Infection

A non-reactive HSV-2 IgG result means you do not have antibodies to HSV-2, indicating you have never been infected with HSV-2 or were tested too early after a recent exposure. 1

Understanding Your Result

Your HSV-2 IgG test came back "non-reactive" (index value <0.90), which has the following implications:

• No HSV-2 infection detected: This result indicates no evidence of past or current HSV-2 infection based on antibody testing. 1
• Your previous herpes was likely HSV-1: Since you report a history of herpes but test negative for HSV-2, your prior infection was most likely HSV-1 (which causes both oral cold sores and can cause genital herpes through oral-genital contact). 1
• HSV-1 is extremely common: Approximately 70% of adults worldwide have HSV-1 antibodies, typically acquired during childhood through non-sexual contact. 2, 1

Critical Timing Consideration: The 12-Week Window

If you had a possible HSV-2 exposure within the past 12 weeks, this negative result may be falsely negative because antibodies take time to develop:

• HSV-2 IgG antibodies develop within several weeks of infection but may not be detectable immediately. 3
• You must wait at least 12 weeks after potential exposure before retesting to allow adequate antibody development. 2, 1
• Testing before 12 weeks can miss early infections during the "window period." 3

What This Means Clinically

• If you have no recent exposure concerns: No specific action is needed regarding HSV-2. 1
• If you have active genital lesions: Serology alone cannot diagnose active lesions—PCR or viral culture of the lesion is the gold standard with 96-98% sensitivity and 95-99% specificity. 2
• Lower transmission risk: A negative HSV-2 result suggests you are not at risk for transmitting HSV-2 genital herpes to partners. 1

Important Caveats About HSV Testing

• Commercial HSV antibody tests can miss infections: Even in patients with proven recurrent HSV-2 infections, commercial antibody tests fail to detect antibodies in 10-30% of cases. 4
• HSV-1 serology has particularly poor sensitivity: Only approximately 70% sensitivity, leading to frequent false-negative results. 2
• If you have recurrent genital lesions despite negative serology: The negative test does not rule out HSV infection—direct testing of lesions with PCR is necessary. 2, 4

When to Retest

• Recent exposure (within 12 weeks): Repeat testing after the 12-week window from exposure. 2, 1
• Exposure more than 12 weeks ago with persistent concern: Consider repeat testing in 4-6 weeks to confirm the result. 2
• Never retest immediately after recent exposure—you must allow the full 12-week antibody development period. 2