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Updated SARS-CoV-2 IgG Serology Testing
Effectively immediately, the Department of Pathology & Laboratory Medicine will update SARS-CoV-2 IgG testing to the Beckman Access SARS-CoV-2 IgG assay. Our own validation study of this assay found clinical specificity of 99.2% (95% CI; 95-100%) and clinical sensitivity of 94% (95% CI; 85-99%). The validation cohort included 120 negative specimens, and 51 positive specimens collected from individuals at least 14 days after an initial PCR test confirmed SARS-CoV-2 infection. A majority of these individuals (n=33) experienced milder symptoms which did not require hospitalization.

Antibody test results should not be interpreted as evidence of immunity. According to the Center for Disease Control and Prevention (CDC), it is not known whether antibodies that result from infection with SARS-CoV-2 provide protection from reinfection, or how long antibodies may provide protection. Positive results may be due to past or present infection with non-SARS-CoV-2 coronavirus strains, such as coronavirus HKU1, NL63, OC43, or 229E.

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 should be considered to rule out infection when symptoms are present or if close contact with an infected individual has recently occurred. 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.

This test has not been reviewed or cleared by the FDA. This test has been authorized by the FDA, under Emergency Use Authorization, for laboratories certified under the Clinical Laboratory Improvement Amendments (CLIA) as qualified to perform high complexity clinical laboratory testing.

Effective date: Sept. 1, 2020

Specimen requirement and testing information:

Specimen: Serum (Red, Gold) / Plasma (Li-Heparin, K2-EDTA)

Methodology and reporting:
Specimens will be tested using an indirect chemiluminescence immunoassay for the qualitative determination of the IgG antibodies against SARS-CoV-2. This assay will be performed on the Beckman DxI800 and will be reported as Nonreactive, Equivocal, or Reactive.

For samples that are reported as Equivocal, retesting on a new sample collected 1-2 weeks later may be recommended if indicated. If the retest is Reactive, this should be considered as evidence of seroconversion due to recent infection.

Test code: COVIG

Minimum stability (after separation from cells):
20-25˚C: 8 hours
2-8˚C: 48 hours
If longer storage is required, freeze at -20˚C or colder.

Some tests may have extended stability beyond stated minimum limits. See directory for details.

Turnaround time (TAT):
Routine: <12 hours
Set Up Days: Daily

Rejection criteria:
Samples containing particulate matter and lipemic or hemolyzed specimens. Specimens that exceed stated stability, unlabeled/mislabeled/mismatched specimens, specimens submitted in leaking containers, or specimens received with insufficient amounts for testing.

  1. Last updated on 4/17/2020
  2. Last updated on 4/17/2020

A summary of all tests offered by our laboratory services can be found here:


Bridgit O. Crews, PhD, DABCC
Clinical Chemistry, Toxicology, & Point of Care Testing

Edwin S. Monuki, MD, PhD
Department of Pathology & Laboratory Medicine
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