Varicella-Zoster IgG (VZV): What Your Result Means

Result guide · Infectious Disease

Content last reviewed 2026-09-12 · Educational information — not medical advice

Quick answer

The varicella-zoster IgG test checks whether you are immune to chickenpox — from a past infection or vaccination. A positive result means you are protected; a negative one means you are susceptible and may need vaccination.

What is Varicella-Zoster IgG (VZV)?

Varicella-zoster virus causes chickenpox and later shingles. The IgG antibody test measures immune memory of the virus. It is used to confirm immunity before exposure risk — for healthcare workers, pregnancy planning, and people unsure whether they ever had chickenpox. A positive result means protection; a negative result means a vaccine could prevent a future infection.

Typical reference interval: Reported as positive (immune) or negative (susceptible), sometimes with a titer value. A clear positive indicates protective immunity; a negative or equivocal result means vaccination should be discussed.. Laboratories differ — the interval printed on YOUR report always governs.

If your Varicella-Zoster IgG (VZV) is high

Common reasons Varicella-Zoster IgG (VZV) runs above the reference interval:

  • Past chickenpox infection — natural infection leaves lifelong antibody — the most common reason for a positive result
  • Varicella vaccination — the vaccine produces the same protective antibody response
  • Recent shingles episode — shingles reactivates the same virus and can boost antibody levels

If your Varicella-Zoster IgG (VZV) is low

Common reasons Varicella-Zoster IgG (VZV) runs below the reference interval:

  • Never had chickenpox or vaccine — no exposure means no protective antibody — the susceptible state
  • Waned immunity — rarely, antibody levels fall over time, though protection often persists
  • Immunosuppression — some immune-suppressing conditions blunt antibody levels

Symptoms worth knowing

The antibody causes no symptoms. A negative result is a susceptibility status, not an illness. In pregnancy especially, knowing immunity matters because chickenpox during pregnancy can be serious.

What usually happens next

  1. A positive VZV IgG means you are immune — no action needed
  2. A negative result means varicella vaccination may be recommended, especially for healthcare workers, teachers, and people planning pregnancy
  3. If you are unsure whether you ever had chickenpox, this test settles it definitively

Get your Varicella-Zoster IgG (VZV) checked

These lab tests measure Varicella-Zoster IgG (VZV) directly. Ordering online takes a few minutes and results arrive securely.

Order VZV IgG Test

We may earn a commission when you order through partner links on the following pages. Educational information here never replaces advice from a qualified healthcare provider.

Related result guides

White Blood Cell Count (WBC) guideLymphocytes guideSedimentation Rate (ESR) guide

Frequently asked questions about Varicella-Zoster IgG (VZV) results

Why do employers test for chickenpox immunity?

In healthcare and childcare settings, susceptible workers can catch and spread chickenpox to vulnerable patients. Confirming immunity (or vaccinating those without it) protects both staff and the people they care for — it is a standard occupational safeguard.

I am pregnant and not immune to chickenpox — what now?

Tell your obstetric provider. They will advise on avoiding exposure and what to do if you are exposed, since chickenpox in pregnancy can be more serious. Vaccination is generally deferred until after pregnancy.

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