COVID-19 Progress Note (Qualitative Antibody Test)
This test checks for antibodies in your blood that your immune system makes after exposure to COVID-19. Antibodies can appear days to weeks after infection, helping your body fight the virus.
["Assesses immune response to past COVID-19 exposure."]
Key facts at a glance
- LOINC
- 100459-7
- Short code
- OP COVID-19 Progress note
- Synonyms
- OP COVID-19 Progress note
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- role
- 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
This test detects specific antibodies (immunoglobulins) produced by your immune system in response to the SARS-CoV-2 virus. Antibodies like IgG and IgM are common targets, though the exact types may vary by test. The presence of these antibodies suggests your body has encountered the virus, either through infection or vaccination.
How the Test Works
The test uses a blood sample drawn from your arm. Lab technicians analyze a small portion of your serum or plasma to identify antibodies through an immunoassay method. This process may involve detecting antibody binding to viral proteins or antigens, often visualized as a color change or signal detection.
When You Might Need This Test
Healthcare providers may order this test to evaluate your immune response if you’ve had COVID-19 symptoms, recovered from infection, or received a COVID-19 vaccine. It can also be used to monitor immunity in certain high-risk groups or after exposure to the virus.
What the Results Mean
A positive result indicates the presence of antibodies, suggesting your immune system has recognized the virus. However, antibody levels can vary widely and may decline over time. A negative result means no detectable antibodies were found, which doesn’t definitively rule out past infection or immunity.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Antibody testing can help determine if you’ve had COVID-19, which may be important for travel, workplace safety, or vaccine eligibility. However, antibodies alone do not guarantee long-term immunity. This test is often used alongside other criteria (like symptoms or medical history) to assess risk or exposure history.
Short name
COVID-19 Antibody Screening
Frequently asked questions
Why might my test results be positive even if I never had COVID-19?
Can antibodies protect me from getting COVID-19 again?
What should I do if my antibody test is negative but I suspect I had COVID-19?
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