Description of the blood test:

The Varicella-Zoster Virus (VZV) IgG test is a serological study used to detect “memory” antibodies against the virus that causes both chickenpox (Varicella) and shingles (Herpes Zoster). After a person recovers from chickenpox, the virus remains dormant in the nervous system for life. The presence of IgG antibodies indicates that the body has either survived a natural infection in the past or has been successfully vaccinated. In clinical practice, this test is essential for verifying a person’s immune status to ensure they are protected from reinfection or to assess the risk of developing shingles later in life.

What does the analysis represent?

• Purpose: Quantitative or qualitative determination of IgG antibodies to VZV in blood serum.
• Primary application: Confirmation of post-vaccination immunity, verifying past history of chickenpox, and screening for immunity in pregnant women or healthcare workers.
• Performance: High-precision enzyme immunoassay (ELISA) of a venous blood sample.

Recommendations for the test (General)

• Time: Blood collection is recommended in the morning.
• Fasting: A food intake pause of 4–8 hours is preferred.
• Rest: Stay in a calm state for 15–20 minutes before the procedure.
• Important: This test confirms long-term protection; it is not used to diagnose an active, spreading rash (for that, IgM or PCR is used).

What can affect the results?

• Immune Status: Immunocompromised individuals may show lower antibody titers despite previous exposure or vaccination.
• Medical History: Recent treatment with immunoglobulins or blood transfusions may temporarily affect the accuracy of the antibody levels.

When to take the test?

• Recommendations: Prescribed for individuals who do not remember having chickenpox, women planning a pregnancy, and patients about to start immunosuppressive therapy.
• Preparation: Standard preparation for serological tests; avoid alcohol 24 hours prior.

How to interpret the results?

The interpretation of data is the exclusive responsibility of an infectious disease specialist or a neurologist. The level of VZV IgG antibodies is a marker of immune memory and is not a final diagnosis of your current health. The physician evaluates whether the titer is high enough to provide protective immunity. Only an expert can determine if your current immune profile protects you from the virus or if a booster vaccination is necessary to prevent a future outbreak of shingles.

Possible further investigations

VZV IgM: If an active rash or suspected shingles reactivation is present.
VZV PCR: For direct detection of the virus from skin lesions.
Consultation with a Neurologist: To discuss the risk of shingles and post-herpetic neuralgia, especially for patients over 50.
Complete Blood Count (CBC): To evaluate overall immune health.

When does the next step make sense? 

Confirming your VZV immunity is a vital part of proactive health management. If the result is negative (meaning you have no protection), the next step is a consultation to discuss a vaccination plan to prevent severe adult-onset chickenpox or future shingles complications.

👉 If necessary, you can discuss the test results with our specialized — neurologist (Doctors – TAMC).