Skip to content

Fluorescent Antibody Assay for Antibodies Against Varicella-Zoster Virus (IgG)

Published: August 9, 2026Updated: August 16, 2026

This test measures the level of Immunoglobulin G (IgG) antibodies in your blood to the varicella-zoster virus (VZV), which causes chickenpox and shingles. It helps determine if your immune system has been exposed to the virus.

Quick summary

["Assesses past exposure to chickenpox or shingles virus through antibody detection."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
6637-3
Short code
FLUAV Vic Ab Ser HAI-aCnc
Synonyms
FLUAV Vic Ab Ser HAI-aCnc
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
hai
Specimen volume
5 mL
Stability
Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
500
Lipemia max
1000
Icterus max
500
TAT
4–24 hours
Order
routine

Why This Test Is Done

Your healthcare provider may order this test to check if you have developed immunity to chickenpox or shingles after exposure, vaccination, or natural infection. It can also help diagnose or monitor conditions like shingles or confirm exposure in outbreaks.

What to Expect Before the Test

No special preparation is needed. A blood sample will be drawn from a vein, typically in your arm. You may feel a slight pinch, but it usually doesn’t cause significant discomfort.

What the Test Results Mean

Positive results indicate the presence of IgG antibodies, suggesting past exposure to the virus. However, this does not guarantee immunity, as antibody levels can decline over time. Negative results mean no detectable antibodies, indicating no prior exposure.

Common Reasons for Testing

This test is often used in healthcare settings to screen individuals for immunity before procedures that may involve exposure to varicella-zoster virus, such as blood transfusions or surgeries. It’s also used in outbreaks or after suspected exposure to confirm infection history.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

High IgG levels suggest a history of chickenpox or shingles, but they don’t always mean you’re immune for life. Antibody levels can decrease over time, so periodic testing may be recommended. If you’re at high risk for complications (e.g., immunocompromised individuals), your provider may advise vaccination or booster shots if needed.

Short name

IgG Antibody to Varicella-Zoster Virus (VZV) Fluorescent Antibody

Frequently asked questions

What does a positive test result mean for my health?
A positive result means your immune system has likely encountered the virus before, producing IgG antibodies. This indicates past exposure but does not guarantee protection against future infection. If you’re unsure about vaccination status or risk, discuss this with your healthcare provider.
Can this test detect active shingles?
No, this test specifically measures antibodies for past exposure, not active infection. For diagnosing shingles, your provider may use other tests or clinical evaluation, including symptoms and possibly a shingles-specific antibody test.
Is there any risk or discomfort with this blood test?
The blood draw is quick and generally well-tolerated. You may feel slight discomfort or bruising at the site, but serious risks are rare. If you have a bleeding disorder or are on blood thinners, let your provider know before the test.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy