SARS CoV-2 anti-N antibody is produced within weeks of natural infection. Checking serology using a qualitative anti-N IgG assay, three to four weeks after the onset of symptoms optimises the accuracy of testing and can determine if a person has been exposed to, and produced detectable antibodies to the virus that cause COVID-19 infection.
SARS-CoV-2 anti-Nucleocapsid
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SARS-CoV-2 anti-Nucleocapsid
Resolving or past COVID-19 infection can be identified using serologic testing for the presence of anti-N antibody.
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Clinical Details
Infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) initiates a cell-mediated and humoral immune response that produces antibodies against specific viral antigens such as the nucleocapsid (N) protein and spike (S) protein. These include anti-S protein antibodies that target the spike’s S1 protein subunit and receptor binding domain (RBD). Antibody tests can detect the presence of these antibodies in serum within days to weeks following acute infection.
SARS-CoV-2 antibodies are an excellent indicator of past COVID-19 infection and therefore helps determine the proportion of a population that has been previously exposed or infected. The Nucleocapsid Protein (N Protein) of severe acute respiratory syndrome Coronavirus 2 (SARS-CoV2) is located in the viral core. Immunoglobulin G (IgG) targeting N protein is detectable in the serum of infected or previously patients.
SARS-CoV-2 antibody tests are not used to diagnose current or active infection. Antibody tests can identify persons with resolving or past SARS-CoV-2 infection and thereby help scientists and public health experts better understand the epidemiology of SARS-CoV-2.
Case Study
Delivering True Innovation
At Enfer Medical, we have integrated a cutting-edge and fully automated WASPLab® (Walk Away Specimen Processor) that has significantly enhanced our testing capabilities to ensure the highest of quality when processing patient samples.
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Health & Wellness
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Sexual Health
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Respiratory Health
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Reproductive & Female Health
Hormonal analysis is hugely beneficial to identifying problems that can arise during the reproductive years.
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Sample Type &
Volume Required
5mL venous serum or plasma.
Enfer Medical
Tests/Assays
The SARS-CoV-2 anti-Nucleocapsid IgG test offered by Enfer Medical is carried out using an immunoassay for the qualitative determination of anti-N antibody to SARS-CoV-2 in human serum. This test is CE-IVD certified.
Patient
Request Form
For clients using the Enfer Medical Client Portal, the Enfer Medical Patient Request Form (PRF) will be generated when you have completed your “Test Request” within the portal linked below.
Please note that samples suspected of containing high risk pathogens such as Mycobacterium tuberculosis should be clearly identified on the form and packed separately from other samples.
24 hours
Results are available next working day.
7 Days a Week
This assay is available seven days a week.
Packaging
The packaging/preparation of samples for delivery to the laboratory are required to be in adherence to all national regulations for the safe transport of biological materials. HSE guidance can be reviewed HERE.
There are specific packaging instructions and labelling requirements requiring triple packaging including:
- Primary leak-proof container – tube or vial containing the sample.
- Secondary watertight container, with absorbent material, intended to protect the primary container.
- Outer container protects the secondary container.
- Patient Request forms must be placed between the secondary container and the outer shipping container.
Further information on the packaging/preparation of samples for delivery to the laboratory is contained within the Enfer Medical Laboratory User Manual which clients are provided with.
Storage & Stability
Samples must be tested within 4 hours of collection if stored at room temperature. Samples must be tested within 4 days of collection if stored at 2-8°C.
Transporting
Samples
Samples
In addition to the packaging of samples, the transport/delivery of clinical samples to the laboratory is required to be in adherence to all national regulations for the safe transport of biological materials. Enfer Medical provides a fully compliant logistics service, aligned with clients’ testing requirements.
Prompt transport of specimens:
To ensure prompt testing of samples and release of results within the published test turnaround times, samples should arrive to the laboratory by 18:00. Test turnaround time is measured from receipt of the sample at the laboratory until the time the authorised results are reported to users.
Acceptance/Rejection
of Samples
of Samples
In rare cases specimens may not be suitable for testing on arrival to the laboratory. In that case the sample will be rejected at the receipt stage and the service user will be notified immediately and an explanation as to why the sample could not be processed will be provided. Reasons why samples cannot be processed include but are not limited to:
- Samples received beyond the stability limits and/or not at the correct temperature indicated for each test.
- Incorrect sample type received.
- Leaking samples, sample not received or sample insufficient for analysis as stated below within sample requirements.
- Non-compliant samples or request forms i.e. those missing sample date information, missing sample test request and/or missing sample site/type information.
- Samples received without the necessary patient identifiers.
Clients will be provided with guidance on Sample Receipt Anomalies.
Our Services
Service
Health & Wellness
General health and wellness testing can include a variety of tests, depending on the needs of the individual or recommendations of
Find Out More
Service
Sexual Health
Regular STI screening facilitates early treatment and reduces the long-term consequences of infection.
Find Out More
Service
Respiratory Health
Rapid early pathogen identification has important treatment and infection control implications. See our range of tests here.
Find Out More
Service
Reproductive & Female Health
Hormonal analysis is hugely beneficial to identifying problems that can arise during the reproductive years.
Find Out More
Result Values:
Qualitative results for SARS-CoV-2 IgG will be reported as:
Qualitative Result:
- < 50.0 AU/mL - NEGATIVE
- ≥ 50.0 AU/mL - POSITIVE
- INVALID
A positive result indicates that a person had an immune response to the COVID-19 virus and were likely to have had previous exposure to the virus. A negative result means there is no evidence the person was previously infected with COVID-19. However, this does not completely rule out past infection, it simply means there are no antibodies currently or remaining in the person's system.
Accessing
Your Results
Following receipt at the Laboratory, results should be available on the next working day and will be reported to the referring clinician via the Enfer Medical Client Portal or in a format agreed with clients.
Established clients can login to the portal using the link above.
Our Services
Service
Health & Wellness
General health and wellness testing can include a variety of tests, depending on the needs of the individual or recommendations of
Find Out More
Service
Sexual Health
Regular STI screening facilitates early treatment and reduces the long-term consequences of infection.
Find Out More
Service
Respiratory Health
Rapid early pathogen identification has important treatment and infection control implications. See our range of tests here.
Find Out More
Service
Reproductive & Female Health
Hormonal analysis is hugely beneficial to identifying problems that can arise during the reproductive years.
Find Out More