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Covid Antibody Test | Blood Test for Covid 19

Test Code: 403607P
IgG and IgM blood-based serology testing may help to identify people who have been exposed to COVID-19 SARS-CoV-2, and may have developed some level of immunity but potentially have mild to no symptoms.

To build this test in your HL7 Interface, please reach out to for the build information.

Patients, you must contact your physician to order antibody testing for Coronavirus COVID-19.
Viracor will not see patients at our facility or collect samples on site.

An account must be set up to order testing. See Specimen Information Section for more information.


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Clinical and Procedure
Clinical Utility

The Coronavirus SARS-CoV-2 COVID-19 IgG antibody lab test is for the detection of IgG antibodies against SARS-CoV-2 from human clinical specimens.

The Coronavirus SARS-CoV-2 COVID-19 IgM antibody lab test is for the detection of IgM antibodies against SARS-CoV-2 from human clinical specimens.

Negative results do not rule out SARS-CoV-2 infection, particularly in those who have been in contact with the virus. Follow-up testing with a molecular diagnostic assay should be considered to rule out infection in these individuals. Results from antibody testing should not be used as the sole basis to diagnose or exclude SARS-CoV-2 infection or to inform infection status.

About Coronavirus SARS-CoV-2 and COVID-19

Please refer to the CDC website for the most up to date information on SARS-CoV-2 or COVID-19 at

At the end of 2019, an outbreak of the virus initially referred to as 2019 novel Coronavirus, later identified as SARS-CoV-2, occurred in Wuhan, Hubei Province, China. A betacoronavirus, like MERS-CoV and SARS-CoV, the virus originates from bats. As of January 30, 2020, the International Health Regulations Emergency Committee of the World Health Organization declared a “public health emergency of international concern.”

The disease caused by SARS-CoV-2 has been named coronavirus disease 2019, abbreviated as COVID-19. Main symptoms of the disease include fever, cough and shortness of breath. The CDC recommends reaching out to a physician if you develop symptoms and have been in close contact with a person known to have COVID-19; or if you have recently traveled from an area with widespread or ongoing community spread of COVID-19. The virus is spread via person-to-person contact through respiratory droplets produced when a person coughs or sneezes. The best preventative measures are to avoid close contact with people who are sick; avoid touching nose, eyes and mouth; cover a cough or sneeze with a tissue and discard immediately; and clean and disinfect frequently touched objects and surfaces using a household cleaning spray or wipe. Washing your hands with soap and water for at least 20 seconds frequently is one of the best preventative measures and hand sanitizer can be used when soap and water are not available.

About SARS-CoV-2 COVID-19 Antibody Testing

Unlike RT-PCR tests, which directly detect the presence of SARS-CoV-2 for approx. 1 – 3 weeks after infection, blood-based serology assays detect antibody responses to this virus. Serological testing has the ability to consistently identify people who were recently infected or exposed, even if they are no longer shedding the virus. Individuals will typically have detectable antibodies for weeks to months after infection regardless if mild or no clinical signs were present. Antibodies to SARS-CoV-2 may also provide immunity to COVID-19 although the antibody levels required for protection and the duration of this immunity has not been defined. IgM testing is  recommended as early as 5 days after infection, and IgG testing is recommended at least 12-14 days after potential exposure – giving the body the time it needs to build an immune response and produce antibodies. Over time, antibody testing is likely to become a crucial next step in fighting the spread of the virus.



The Gold Standard Diagnostics SARS-CoV-2 IgG ELISA Test Kit is intended for the qualitative detection of IgG antibodies to SARS-CoV-2 virus in human serum to aid in the diagnosis of Coronavirus (COVID-19).

During the test procedure, antibodies to SARS-CoV-2, if present in the human serum sample will bind to the antigens coated onto the wells forming antigen-antibody complexes. Excess antibodies are removed by washing. A conjugate of goat anti-human IgG antibodies conjugated with horseradish peroxidase are then added, which binds to the antigen-antibody complexes. Excess conjugate is removed by washing. This is followed by the addition of a chromogenic substrate, tetramethylbenzidine (TMB). If specific antibodies to the antigen are present in the patients’ serum, a blue color will develop. The enzymatic reaction is then stopped with a stopping solution causing the contents of the well to turn yellow. The wells are read photometrically with a microplate reader at 450nm.

This test was developed and its performance characteristics determined by Eurofins Viracor. It has not been reviewed, cleared or approved by the U.S. Food and Drug Administration (FDA). The FDA has determined that such clearance is not necessary. This test is used for clinical purposes. It should not be regarded as investigational or for research. Results should be used in conjunction with clinical findings, and should not form the sole basis for a diagnosis or treatment decision.

SARSG-CoV-2 IgG ELISA Package Insert


The SCoV-2 Detect™ IgM ELISA is a qualitative indirect ELISA for the detection of IgM antibodies targeting epitopes derived from SARS-CoV-2. Diluted serum specimens are added to antigen-coated wells and incubated. After incubation and washing, human antibodies targeting SARS-CoV-2 antigens remain bound to the plate surface. Secondary antibody conjugated to horseradish peroxidase (HRP) targeting human IgM is then added to each well. After incubation, the ELISA wells are washed once again before a tetramethylbenzidine (TMB) substrate is added. An acidic stopping solution is finally used to stop the reaction and the degree of enzymatic turnover of the substrate is determined by absorbance measurement at 450 nanometers.

This test has not been FDA cleared or approved; this test has been authorized by FDA under an EUA for use by laboratories certified under CLIA to perform high complexity tests.

SCoV-2 Detect™ Emergency Use Authorization Letter

SCoV-2 Detect™ IgM ELISA Package Insert

SCoV-2 Detect™ Fact Sheet for Health Care Providers

SCoV-2 Detect™ Fact Sheet for Recipients


The specificity was determined by testing healthy blood donor samples which were collected prior to the COVID-19 outbreak (collected before 2019) on the Gold Standard Diagnostics SARS-CoV-2 IgG ELISA Test Kit. The specificity was 100.0% for donors in the US and 100.0% for donors in Germany.

Cross-reactivity of the SCoV-2 Detect™ IgM ELISA Kit was be evaluated by testing SARS-CoV-2 seronegative specimens from patients with antibodies to other viral infections and autoantibodies which could potentially cause false positive results. One hundred eighty normal human serum (NHS) samples that were collected in the US prior to the COVID-19 outbreak (i.e. known negatives) were also tested. SCoV-2 Detect™ IgM ELISA demonstrates no cross-reactivity against IgM antibodies for influenza A, influenza B, hepatitis B, hepatitis C, human immunodeficiency, respiratory syncytial viruses or anti-nuclear antibodies or rheumatoid factor or human anti-mouse antibody. 178 of 180 NHS tested negative.

Turnaround Time

During this unprecedented time of high volume, the turnaround time for most Coronavirus SARS-CoV-2 (COVID-19) samples is 24 hours from receipt of specimen in the lab, Monday through Saturday.  As daily volume can have an impact on workflow, we are monitoring this closely and will provide updates as the situation changes.

Specimen Information
Specimen Type Order Code CPT Code NY Approved Volume Assay Range Special Instructions
Serum (1) 403607P 86769 (x2) Yes

1 mL (0.5 mL minimum)


Unit value of less than 9.0 indicates there was no detectable antibody present. The result does not rule out SARS-CoV-2 infection. Follow-up testing with a molecular diagnostic should be considered to rule out infection. Unit values between 9.0 and 11.0 indicate initial evidence for detection of antibodies and additional testing is recommended. Serological evidence is best obtained by testing of paired acute and convalescent phase samples obtained several weeks apart. A value of greater than 11.0 indicates antibodies have been detected.


Immune Status Ratio (ISR) value of less than 1.0 indicates there was no detectable IgM antibody present. The result does not rule out SARS-CoV-2 infection, particularly in those who have been in contact with the virus. Follow-up testing with a molecular diagnostic should be considered to rule out infection. ISR value of 1.0 or greater indicates antibodies to SARS-CoV-2 have been detected. Positive sera must take into account other clinical findings and be confirmed with other tests if indicated.

  • Collect whole blood in a SST, red top, or tiger-top serum tube.
  • Allow blood to clot at room temperature for 30-60 minutes then centrifuge to recover serum.
  • Samples are stable refrigerated for 7 days or longer when frozen.
  • Recommend shipping samples frozen.

To Setup an Account:
Prior to sending samples for the first time, all new clients must set up a Viracor Account. Please visit our Account Setup page to begin this process.

Ship Monday through Friday. Friday shipments must be labeled for Saturday delivery. All specimens must be labeled with patient's name and collection date. A Viracor test requisition form must accompany each specimen. For additional testing, please send a separate specimen. Refer to our website for refer to our website for accepted specimen types. Ship specimens FedEx Priority Overnight® to: Eurofins Viracor, 1001 NW Technology Dr, Lee's Summit, MO 64086.

Causes for Rejection

Whole blood frozen, specimens beyond their acceptable length of time from collection as listed in the specimen handling, or specimen types other than those listed. Hyperlipemic and moderate to grossly hemolyzed specimens.


Specimens are approved for testing in New York only when indicated in the Specimen Information field above.

The CPT codes provided are based on the performing laboratory's interpretation of the American Medical Association's Current Procedural Terminology (CPT) codes and are provided for informational purposes only. CPT coding is the sole responsibility of the billing party. Questions regarding coding should be addressed to your local Medicare carrier. Viracor assumes no responsibility for billing errors due to reliance on the CPT codes illustrated in this material.

We will continue to follow federal and state requirements for both notification of results and any confirmatory testing that is required by another agency.


Center for Disease Control and Prevention.

  1. Zhou et al. (2020) A pneumonia outbreak associated with a new coronavirus of probable bat origin, Nature, 579: 270-273
  2. Woo et al. (2004) Detection of Specific Antibodies to Severe Acute Respiratory Syndrome (SARS) Coronavirus Nucleocapsid Protein for Serodiagnosis of SARS Coronavirus Pneumonia, Journal of Clinical Microbiology, 42:2306-2309
  3. Xiao et al. (2020) Evolving status of the 2019 novel coronavirus infection: Proposal of conventional serologic assays for disease diagnosis and infection monitoring, Journal of Medical Virology, 92:464–467.
  4. Okba et al. (2020) SARS-CoV-2 specific antibody responses in COVID-19 patients, medRxiv 2020.03.18.20038059; doi:
  5. Li, X., Geng, M., Peng, Y., Meng, L., & Lu, S. (2020). Molecular immune pathogenesis and diagnosis of COVID-19. Journal of Pharmaceutical Analysis.
  6. Okba, N. M. A., Muller, M. A., Li, W., Wang, C., GeurtsvanKessel, C. H., Corman, V. M., Lamers, M. M., Sikkema, R. S., de Bruin, E., Chandler, F. D., Yazdanpanah, Y., le Hingrat, Q., Descamps, D., Houhou-Fidouh, N., Reusken, C. B. E. M., Bosch, B.-J., Drosten, C., Koopmans, M. P. G., & Haagmans, B. L. (2020). SARS-CoV-2 specific antibody responses in COVID-19 patients. MedRxiv, 2020.03.18.20038059.
  7. Okba, N. M. A., Muller, M. A., Li, W., Wang, C., GeurtsvanKessel, C. H., Corman, V. M., et al. (2020). Severe Acute Respiratory Syndrome Coronavirus 2−Specific Antibody Responses in Coronavirus Disease 2019 Patients. Emerging Infectious Diseases, 26(7).
  8. Udugama, B., Kadhiresan, P., Kozlowski, H. N., Malekjahani, A., Osborne, M., Li, V. Y. C., Chen, H., Mubareka, S., Gubbay, J., & Chan, W. C. W. (2020). Diagnosing COVID-19: The Disease and Tools for Detection. ACS Nano.
  9. Wölfel, R., Corman, V.M., Guggemos, W., Seilmaier, M., Zange, S., Müller, M.A., et al. (2020). Virological assessment of hospitalized patients with COVID-2019. Nature.
  10. Wu, F., Zhao, S., Yu, B., Chen, Y.-M., Wang, W., Song, Z.-G., Hu, Y., Tao, Z.-W., Tian, J.-H., Pei, Y.-Y., Yuan, M.-L., Zhang, Y.-L., Dai, F.-H., Liu, Y., Wang, Q.-M., Zheng, J.-J., Xu, L., Holmes, E. C., & Zhang, Y.-Z. (2020). A new coronavirus associated with human respiratory disease in China. Nature, 579(7798), 265–269.
  11. Yong, S.E.F., Anderson, D.E., Wei, W.E., Pang, J., Chia, W.N., Tan, C.W., et al. (2020). Connecting clusters of COVID-19: an epidemiological and serological investigation. The Lancet Infectious Diseases.
  12. Zhou, P., Yang, X.-L., Wang, X.-G., Hu, B., Zhang, L., Zhang, W., Si, H.-R., Zhu, Y., Li, B., Huang, C.-L., Chen, H.-D., Chen, J., Luo, Y., Guo, H., Jiang, R.-D., Liu, M.-Q., Chen, Y., Shen, X.-R., Wang, X., … Shi, Z.-L. (2020). A pneumonia outbreak associated with a new coronavirus of probable bat origin. Nature, 579(7798), 270–273.
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