Quick Answer
Herpes IgG blood tests are accurate when done at the right time (12-16 weeks post-exposure). Type-specific tests distinguish HSV-1 from HSV-2. False positives occur at low index values, and confirmatory testing is recommended for borderline results.
- Window period: 12-16 weeks for reliable IgG results
- Accuracy: >95% sensitivity and specificity for HSV-2 IgG
- False positives: common at index values 1.1-3.5
- IgM tests: unreliable, should NOT be used for diagnosis
Context Most Pages Skip
Herpes testing is controversial because of the psychological impact of a positive result. The CDC does not recommend routine screening for asymptomatic people.
When to test
Testing is appropriate for people with symptoms, partners of people with herpes, and those who specifically request it. Results should be interpreted with caution, especially at low index values.
⚕️ This page is educational and does not replace advice from a licensed clinician. If you may have been exposed to an STI, get tested — most infections are manageable, and many are fully curable.
Sources & Further Reading
- CDC — Sexually Transmitted Infections
- CDC STI Treatment Guidelines
- WHO — Sexually transmitted infections fact sheet
- MedlinePlus — Sexually Transmitted Diseases
Figures reflect CDC surveillance and WHO estimates; they are population statistics, not personal risk predictions.