Hepatitis B Core Antibody, Qualitative (Serum)
This test detects antibodies to the hepatitis B core antigen, which may indicate past or current hepatitis B infection.
["This test helps determine if you’ve been exposed to hepatitis B virus."]
Key facts at a glance
- LOINC
- 22318-0
- Short code
- HBV core IgG Ser-aCnc
- Synonyms
- HBV core IgG Ser-aCnc
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 82784
- 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
What This Test Measures
The test looks for antibodies (specifically IgM and IgG) against the hepatitis B core antigen. These antibodies develop after the body encounters the virus. IgM antibodies often appear early in infection, while IgG antibodies persist longer, indicating immunity or past infection.
Why It’s Done
Doctors may order this test to screen for hepatitis B, evaluate exposure risk, assess immunity status, or monitor chronic infection. It’s also used in newborn screening to prevent mother-to-child transmission.
Sample Collection and Preparation
A blood sample is drawn from a vein in your arm. The serum portion is tested for antibodies. Results are reported as positive or negative, not with a numeric value.
Interpreting Your Results
A positive result means you have antibodies against hepatitis B core antigen, suggesting past infection or immunity. A negative result means no detectable antibodies were found at this time.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Short name
Hepatitis B Core Antibody (Qualitative)
Frequently asked questions
Positive results may indicate immunity from prior infection or vaccination, but ongoing monitoring may still be recommended. Chronic infection requires further evaluation by a healthcare provider to guide treatment.
A positive result means your body has produced antibodies to the hepatitis B core antigen, which could mean you’ve had the virus in the past or are immune due to vaccination. This does not necessarily mean you’re currently infected, but it does mean your immune system has recognized the virus.
Yes, if you’re not already vaccinated, a positive test does not prevent vaccination. Vaccination is safe and recommended for those who haven’t received it, regardless of prior antibody status.
Sources
- 1
- 2Lab Tests OnlineSource
- 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 16, 2026. · Read our editorial policy