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GTR Home > > SARS-CoV-2 Total Nucleocapsid Antibody (IgG, IgA, and IgM) - Biorad Assay


Test order codeHelp: 234

Test name


SARS-CoV-2 Total Nucleocapsid Antibody (IgG, IgA, and IgM) - Biorad Assay

Purpose of the test


This is a clinical microbial test intended for Help: Screening



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Click Indication tab for more information.

How to order


Online through physician request drawn at the office or in one of our collection sites CPT Code: 86769
Order URL Help: https://www.ksldx.com/covid-19-antibody-test

Specimen source


Turnaround time

24 -48 hours


OAntibody assay
Enzyme-Linked Immunosorbent Assays (ELISA)

Summary of what is tested

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Click Methodology tab for more information.

Clinical utility


Not provided

Clinical validity


Not provided

Comments about the test interpretation (e.g. clinical implication of test results)

SARS-Cov-2 total antibody assay detects IgM, IgG and IgA antibodies to nucleocapsid proteins of SARS-CoV-2 virus. A Positive result by this assay indicates recent or prior exposure to the virus. False positive results with may occur with this assay due to cross reactivity from pre-existing antibodies or other possible causes. A negative or equivocal finding does not preclude acute infection. If acute infection is suspected, direct testing for SARS-CoV-2 is indicated. Antibodies to SARS-CoV-2 are generally detectable in blood several days after infection, though the duration of time the antibodies are present post infection is not well characterized. It is unknown how long antibodies to SARS-CoV-2 will remain present in the blood after infection and it is not known if they confer immunity to infection. The positive percent agreement in 51 serum specimens collected between 2-42 days post onset of clinical symptoms compared to SARS-CoV-2 RT-PCR was 92.16% and negative percent agreement is 99.56% (Platelia SARS-CoV-2 Total Ab package insert, Bio-Rad Laboratories, Inc.). Another study reported a specificity and sensitivity of 97.4% and 94.9% for total antibodies using the adapted cut‐offs (≥ 0.8) with this assay (Tré-Hardy M, Wilmet A, Beukinga I, Favresse J, Dogné JM, Douxfils J, Blairon L. Analytical and clinical validation of an ELISA for specific SARS-CoV-2 IgG, IgA, and IgM antibodies. J Med Virol. 2021 Feb;93[2]:803-811).

Clinical resources

Practice guidelines

  • NICE, 2024
    UK NICE Guideline NG191, COVID-19 rapid guideline: managing COVID-19, 2024

Consumer resources

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