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GTR Home > > DiaSorin LIAISON® SARS-CoV-2 S1/S2 IgG Test


Test name


DiaSorin LIAISON® SARS-CoV-2 S1/S2 IgG Test

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


Order URL Help: https://makoexchangedev.com/covid19-ereq/

Specimen source


Sample requirements

Either human serum or plasma may be used. The anticoagulants sodium heparin, lithium heparin, and potassium EDTA may be used with this assay. Follow the tube manufacturers’ instructions carefully when using collection containers. Blood should be collected aseptically by venipuncture and the serum or plasma separated from clot, red cells, or gel separator, after centrifugation. Before shipping specimens, serum or plasma specimens should be removed from clot, red cells, or gel separator. Specimens may be shipped in dry ice (frozen), in wet ice (2-8 C) or at room temperature (20-25 C); if the assay is performed within seven days of sample collection, the samples removed from red cells, clot or gel separator may be kept at 2-8 C; otherwise they should be aliquoted and stored deep-frozen (–20 C or below). Uncontrolled transport conditions (in terms of temperature and time) can cause inaccurate analytical results.


OAntibody assay
Chemiluminescent Immunoassay (CIA)
  • LIAISON® XL Analyzer (DiaSorin, Inc.)

Summary of what is tested

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Clinical utility


Not provided

Clinical validity


Clinical sensitivity: Total IgG positive results from 76 patients SARS-CoV-2 PCR positive from 3 hospitals shown as days from diagnosis (percent samples tested; 95% CI - Positive Percent Agreement with PCR Comparator): ≤ 5 days (25%; 14.57% - 39.44%), 6-14 days (89.80%; 78.24% - 95.56%), ≥15 days (97.56%; 87.40% - 99.57%). Clinical specificity: Presumed SARS-CoV-2 negative samples (n=1090) collected prior to COVID-19 were tested; 1082 out of 1090 were negative resulting in 99.3% clinical specificity (95% CI: 98.6 – 99.6%).


Not provided

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

The analyzer automatically calculates SARS-CoV-2 S1/S2 IgG antibody concentrations expressed as arbitrary units (AU/mL) and grades the results. Assay range. Up to 400 AU/mL. A negative result (< 15.0 AU/mL) may indicate absence or level of IgG antibodies to SARS-CoV-2 below the limit of detection of this test. A negative result can also be seen in samples taken during an acute infection prior to IgG seroconversion. A positive result (≥ 15.0) indicates the presence of IgG antibodies to SARS-CoV-2 and generally indicates exposure to SARS-CoV-2. Test results are reported qualitatively as positive or negative. However, diagnosis of SARS-CoV-2 infection should not be established on the basis of a single test result, but should be determined in conjunction with clinical findings, patient history, and always in association with medical judgment.

Clinical resources

Practice guidelines

  • NICE, 2022
    UK NICE Guideline NG191, COVID-19 rapid guideline: managing COVID-19

Consumer resources

IMPORTANT NOTE: NIH does not independently verify information submitted to the GTR; it relies on submitters to provide information that is accurate and not misleading. NIH makes no endorsements of tests or laboratories listed in the GTR. GTR is not a substitute for medical advice. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional.