Antibody Screening for SARS-CoV-2 (Serum/Plasma)
This test detects antibodies in your blood that your immune system produces in response to exposure to the virus that causes COVID-19. Antibodies can appear days to weeks after infection, helping your body fight the virus.
This test helps determine if you may have been previously exposed to COVID-19, even if you never had symptoms.
Key facts at a glance
- LOINC
- 97115-0
- Short code
- STUDENTINTHEFEWWEEKSBEFORECOVID19OUTBREAK
- Synonyms
- —
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 3.5
- Ref high
- 5
- Critical range
- 2.5 N/A – 6.5 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 84132
- SNOMED
- 110742001
- 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 Does This Test Measure?
The test measures the presence of antibodies (specifically IgG and sometimes IgM) that your immune system creates after exposure to the SARS-CoV-2 virus. These antibodies are a sign that your body has encountered the virus, either through infection or vaccination.
How Is the Sample Collected?
A blood sample is taken from a vein in your arm by a healthcare professional. You may feel a small pinch when the needle is inserted, but the procedure is quick and usually not painful.
How Soon Can Results Be Available?
Results are typically available within 1 to 3 business days, depending on your healthcare provider’s lab turnaround time. Follow-up instructions from your provider will guide you on interpreting your results.
What Does a Positive Result Mean?
A positive result indicates the presence of antibodies against COVID-19, suggesting you may have been previously infected. This does not confirm a current infection but can help track past exposure, especially useful in understanding immunity or for research purposes.
Reference range
Adult: 3.5-5.0 mmol/LN/A
No special preparation usually required. Stay well hydrated. Inform your healthcare provider of all medications and supplements you are taking.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
This test is primarily used for serological screening, which can help identify individuals who have developed immunity through prior infection. It is not a diagnostic tool for active COVID-19 infection. Positive results may inform vaccination decisions, research studies, or public health tracking but should be interpreted alongside clinical judgment and other tests if needed.
Short name
COVID-19 Antibody Test (Screen)
Frequently asked questions
When Might I Need This Test?
What Does a Negative Result Mean?
Can I Get This Test After Being Vaccinated?
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