Patient Guide to Your Prescribed Diagnostic Test: Understanding the Procedure, Purpose, and Your Results
This test detects IgG antibodies against tick-borne encephalitis virus in blood serum and cerebrospinal fluid to diagnose TBE infection or assess immunity status.
{"Detects IgG antibodies indicating past infection or vaccination immunity","Samples from both blood serum and cerebrospinal fluid may be tested","Positive results suggest protection against tick-borne encephalitis","Performed using immunoassay laboratory technique","Important for patients with exposure risk in endemic areas"}
Key facts at a glance
- LOINC
- 69928-0
- Short code
- TBEV IgG
- Synonyms
- TBEV IgG Index Ser+CSF IA-aCnc
- Category
- cardiac
- Sample
- serum
- Container
- Serum separator tube (SST) or plain red top tube
- Units
- N/A
- Ref low
- 1
- Ref high
- 1.1
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- ≥ 0 years
- Method
- Immunoassay
- CPT
- 86635
- SNOMED
- 122442004
- Specimen volume
- 1.0-2.0 mL serum minimum
- Stability
- Room temperature: 8 hours; Refrigerated (2-8°C): 7 days; Frozen (-20°C or below): 30 days
- Hemolysis max
- 50
- Lipemia max
- 100
- Icterus max
- 20
- TAT
- 24–72 hours
- Order
- routine
What is this test that your doctor has ordered, and how will it help in checking your health condition?
The Tick-Borne Encephalitis (TBE) IgG Antibody Test is a laboratory test that detects IgG antibodies against the tick-borne encephalitis virus in your blood serum and cerebrospinal fluid (CSF). IgG antibodies typically develop 2-3 weeks after infection or vaccination and provide long-term immunity. This test uses an immunoassay technique to measure the antibody index, helping doctors determine if you have been exposed to the TBE virus or if you have developed immunity from vaccination.
Why is this test performed by your healthcare team and what specific health concerns is it designed to address?
This test is performed to: (1) Diagnose tick-borne encephalitis infection in patients with symptoms such as fever, headache, meningitis, or encephalitis, especially after potential exposure in endemic areas of Europe and parts of Asia; (2) Assess immunity status in individuals who have received TBE vaccination; (3) Evaluate patients with neurological symptoms who may have been infected with TBE virus; (4) Support epidemiological surveillance in regions where TBE is prevalent.
How is the test performed at the medical facility, and what can you expect to happen during the appointment?
For this test, a blood sample is collected from a vein in your arm (serum sample). In some cases, a cerebrospinal fluid sample obtained via lumbar puncture may also be tested. The samples are then analyzed in a laboratory using immunoassay techniques to detect and measure TBE-specific IgG antibodies. The antibody index indicates the relative concentration of antibodies in your sample compared to reference values.
Understanding your results involves reviewing the values with your physician, who will interpret them based on normal ranges and your personal medical history.
Results are reported as an antibody index. A positive result indicates the presence of TBE-specific IgG antibodies, which may suggest either a past infection, vaccination, or ongoing immunity. A negative result means no detectable antibodies were found, which could indicate no prior exposure, insufficient time for antibody development, or lack of immunity. Your healthcare provider will interpret these results in the context of your symptoms, vaccination history, and potential exposure risk.
Reference range
Index <1.0: Negative - No detectable IgG antibodies to tick-borne encephalitis virus; Index 1.0-1.1: Equivocal - Borderline antibody levels, recommend repeat testing; Index >1.1: Positive - IgG antibodies to tick-borne encephalitis virus detected, indicating past infection or immunizationN/A
No special preparation required. Patient may eat and drink normally before sample collection. Inform laboratory of any recent tick-borne encephalitis vaccination or exposure to endemic areas.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
The TBE IgG antibody test is clinically significant for diagnosing tick-borne encephalitis, a viral infection that can cause severe neurological complications including meningitis, encephalitis, and myelitis. Early detection is important for proper management. The test also helps assess vaccine response and immunity, particularly for travelers to or residents of endemic areas in Central Europe, Eastern Europe, and Northern Asia. Positive IgG results in CSF samples are particularly important as they indicate intrathecal antibody production, supporting the diagnosis of neuroinvasive TBE infection.
Frequently asked questions
Who should get tested for TBE?
How long does it take for IgG antibodies to appear after infection or vaccination?
Is a positive result always a sign of active infection?
What is the difference between IgM and IgG testing?
Sources
- 1
- 2
- 3
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.
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 10, 2026. · Read our editorial policy