Herpes Simplex Virus 2 (HSV-2) IgG

What is Herpes Simplex Virus 2 (HSV-2) IgG?

This blood test detects IgG antibodies to herpes simplex virus type 2 (HSV-2), the virus most commonly associated with genital herpes.

HSV-2 IgG testing measures type-specific antibodies produced after exposure to herpes simplex virus type 2, which is the leading cause of genital herpes and is transmitted primarily through sexual contact. A reactive result indicates the immune system has encountered the virus at some point, though many people with HSV-2 antibodies have mild, infrequent, or unnoticed symptoms. This test relates to the immune and reproductive systems. Clinicians may order it when evaluating genital sores, clarifying a partner's exposure history, or investigating recurrent symptoms, but major guidelines generally do not recommend routine screening in people without symptoms because of the complexity of interpreting results in low-risk individuals.

Tests often checked alongside this

• HSV-1 IgG — helps clarify oral versus genital exposure patterns
• Herpes Simplex Virus direct testing (swab/PCR) — used to confirm active lesions
• HIV-1/2 Antibodies — often checked together given shared risk factors
• Syphilis RPR — may be assessed alongside when evaluating genital sores

How this can show up in how you look and feel

• Recurrent blisters or sores in the genital or anal area
• Tingling, itching, or discomfort before a visible sore appears
• Flu-like symptoms during a first outbreak, in some people
• Many people with a reactive result have no recognized symptoms at all

What can affect this marker

• Timing of exposure relative to testing, since antibody development takes time
• Immune system status
• Cross-reactivity between HSV-1 and HSV-2 assays in some testing methods
• History of prior outbreaks or diagnosed genital lesions

What to track over time

• Frequency, location, and pattern of any genital symptom recurrences
• Whether a confirmatory test is useful for a borderline or unexpected result
• How outbreak patterns change over time or with stress and lifestyle factors

What to ask your doctor

• What does a reactive HSV-2 result mean given whether or not I've had symptoms?
• How can I reduce the risk of passing this on to a partner?
• Should my partner be tested or informed?
• Are there situations where confirmatory testing would be helpful?

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