Test Catalog

Test Id : COVTA

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), Nucleocapsid, Total Antibody, Serum

Useful For
Suggests clinical disorders or settings where the test may be helpful

Aiding in identifying individuals with an adaptive immune response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), indicating recent or prior infection


This test provides qualitative detection of serum antibodies against the nucleocapsid protein of severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2), the causative agent of coronavirus disease 2019 (COVID-19).


This test will not yield a positive result following vaccination against SARS-CoV-2.


This test is intended for use as an aid in identifying individuals with an adaptive immune response to SARS-CoV-2, indicating recent or prior infection.


Fact sheets for this emergency use authorization (EUA) assay can be found at the following links:

For healthcare providers: www.fda.gov/media/137603/download

For patients: www.fda.gov/media/137604/download

Method Name
A short description of the method used to perform the test

Chemiluminescence Immunoassay (CIA)

NY State Available
Indicates the status of NY State approval and if the test is orderable for NY State clients.


Reporting Name
Lists a shorter or abbreviated version of the Published Name for a test

SARS-CoV-2 Nucleocapsid Total Ab, S

Lists additional common names for a test, as an aid in searching


Coronavirus Ab

Coronavirus antibody



COVID-19 antibody



SARS CoV-2 antibody

Specimen Type
Describes the specimen type validated for testing


Ordering Guidance

Molecular testing is recommended for diagnosis of coronavirus disease 2019 (COVID-19) in symptomatic patients. For more information see:

-COVOO / Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) RNA Detection, Varies

-CVOOA / Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) RNA Detection, Varies

-RSARS / Severe Acute Respiratory Syndrome Coronavirus 2 (SARS CoV-2), Molecular Detection, Varies


For the most up-to-date COVID-19 epidemiology and testing recommendations, visit www.cdc.gov/coronavirus/2019-ncov/index.html

Necessary Information

1. Patient's race and ethnicity, as well as collection date, are required.

2. If ordering electronically, answers must be provided for the order entry questions.

3. If not ordering electronically, patient race and ethnicity must be provided on the request form.


Question ID Description Answers
SRACE Patient's Race American Indian or Alaska Native
Black or African American
Native Hawaiian/Other Pacific Islander
Other Race
Refused to Answer
SETHN Patient's Ethnicity Hispanic or Latino
Not Hispanic or Latino
Not Obtainable
Asked but Unknown

Specimen Required
Defines the optimal specimen required to perform the test and the preferred volume to complete testing

Collection Container/Tube:

Preferred: Serum gel

Acceptable: Red top

Submission Container/Tube: Plastic vial

Specimen Volume: 0.6 mL

Collection Instructions: Centrifuge and aliquot serum within 2 hours of collection.

Specimen Minimum Volume
Defines the amount of sample necessary to provide a clinically relevant result as determined by the Testing Laboratory

0.5 mL

Reject Due To
Identifies specimen types and conditions that may cause the specimen to be rejected

Gross hemolysis Reject
Gross lipemia Reject
Gross icterus Reject

Specimen Stability Information
Provides a description of the temperatures required to transport a specimen to the performing laboratory, alternate acceptable temperatures are also included

Specimen Type Temperature Time Special Container
Serum Refrigerated (preferred) 14 days
Frozen 28 days
Ambient 7 days

Useful For
Suggests clinical disorders or settings where the test may be helpful

Aiding in identifying individuals with an adaptive immune response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), indicating recent or prior infection

Clinical Information
Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an enveloped, single-stranded RNA virus of the family Coronaviridae, genus Betacoronavirus. All coronaviruses share similarities in the organization and expression of their genome, which encodes 16 nonstructural proteins and the 4 structural proteins: spike (S), envelope (E), membrane (M), and nucleocapsid (N).


Results are for the detection of SARS-CoV-2 antibodies. Antibodies to SARS-CoV-2 are generally detectable in blood several days after initial infection; although the duration of time antibodies are present postinfection is not well characterized. Patients may have detectable virus present for several weeks following seroconversion.

Reference Values
Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.


Provides information to assist in interpretation of the test results


No antibodies to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) detected. Negative results may occur in serum collected too soon following infection, in patients who are immunosuppressed, or in patients with mild or asymptomatic infection. This test does not rule out active or recent coronavirus disease 2019 (COVID-19) and will not detect SARS-CoV-2 vaccine-induced antibodies. Follow-up testing with a molecular test is recommended in symptomatic patients.



SARS-CoV-2 antibodies to the nucleocapsid protein detected. Results suggest recent or prior infection with SARS-CoV-2. Correlation with epidemiologic risk factors and other clinical and laboratory findings is recommended. Serologic results should not be used to diagnose recent SARS-CoV-2 infection. Protective immunity cannot be inferred based on these results alone. False-positive results may occur due to cross-reactivity from pre-existing antibodies or other possible causes.

Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances

The sensitivity of Roche Elecsys Anti-SARS-CoV-2 test in early infection is unknown. Negative results do not preclude severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections. If an acute infection is suspected, direct testing for SARS-CoV-2 virus is necessary. See Ordering Guidance.


This test detects total antibodies against the SARS-CoV-2 nucleocapsid protein. All current SARS-CoV-2 vaccines induce antibodies to the spike glycoprotein only. Therefore, this assay will not detect SARS-CoV-2 vaccine induced anti-Spike glycoprotein antibodies and cannot be used to measure vaccine response.


False-positive results for Roche Anti-SARS-CoV-2 IgG test may occur due to cross-reactivity from pre-existing antibodies or other possible causes.


Serum biotin concentrations up to 1200 ng/mL do not interfere with this assay. Extremely high concentrations of biotin in patient serum due to heavy administration or supplementation of biotin may falsely depress anti-SARS-CoV-2 antibody detection.


Performance characteristics have not been established for the following specimen characteristics:

-Potential endogenous interferences eg, hemolysis, bilirubin, rheumatoid factors, and pharmaceutical compounds other than biotin have not been tested and therefore interference cannot be excluded

-Containing particulate matter

-Cadaveric specimens

Clinical Reference
Recommendations for in-depth reading of a clinical nature

1. Zhang W, Du RH, Li B, et al: Molecular and serologic investigation of 2019-nCoV infected patients: implication of multiple shedding routes. Emerg Microbes Infect. 2020 Feb 17;9(1):386-389. doi: 10.1080/22221751.2020.1729071

2. Okba N, Muller MA, Li W, et al: Severe acute respiratory syndrome coronavirus 2-specific antibody responses in coronavirus disease 2019 patients. Emerg Infect Dis. 2020 Apr 8;26(7). doi: 10.3201/eid2607.200841

3. Guo L, Ren L, Yang S, et al: Profiling early humoral response to diagnose novel coronavirus disease (COVID-19). Clin Infect Dis. 2020;ciaa310. doi: 10.1093/cid/ciaa310

4. Wolfel R, Corman VM, Guggemos W, et al. Virological assessment of hospitalized patients with COVID-2019. Nature. 2020 May;581(7809):465-469. doi: 10.1038/s41586-020-2196-x

5. Su S, Wong G, Shi W, et al: Epidemiology, genetic recombination, and pathogenesis of coronaviruses. Trends Microbiol. 2016;24(6):490-502. doi: 10.1016/j.tim.2016.03.003

6. Zhu N, Zhang D, Wang W, et al: A novel coronavirus from patients with pneumonia in China, 2019. N Engl J Med. 2020;382(8):727-733. doi: 10.1056/NEJMoa2001017

7. Liu L, Liu W, Zheng Y, et al: A preliminary study on serological assay for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in 238 admitted hospital patients. Microbes Infect. 2020;S1286-4579(20)30086-1. doi: 10.1016/j.micinf.2020.05.008

8. Zhang W, Du RH, Li B, et al: Molecular and serologic investigation of 2019-nCoV infected patients: implication of multiple shedding routes. Emerg Microbes Infect. 2020 Feb 17;9(1):386-389. doi: 10.1080/22221751.2020.1729071

Method Description
Describes how the test is performed and provides a method-specific reference

The Roche Elecsys anti-SARS-CoV-2 assay uses a recombinant protein representing the nucleocapsid (N) antigen for the determination of antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In the first incubation the sample, biotinylated SARS-CoV-2-specific recombinant antigen and SARS-CoV-2-specific recombinant antigen labeled with a ruthenium complex form a sandwich complex. During the second incubation, after addition of streptavidin-coated microparticles, the complex becomes bound to the solid phase via interaction of biotin and streptavidin. The reaction mixture is aspirated into the measuring cell where the microparticles are magnetically captured onto the surface of the electrode. Unbound substances are then removed. Application of a voltage to the electrode induces chemiluminescent emission, which is measured by a photomultiplier. Results are determined automatically by the software by comparing the electrochemiluminescence signal obtained from the reaction product of the sample with the signal of the cutoff value previously obtained by calibration.(Package insert: Elecsys Anti-SARS-CoV-2. Roche Diagnostics; v 4.0. 08/2020)

PDF Report
Indicates whether the report includes an additional document with charts, images or other enriched information


Day(s) Performed
Outlines the days the test is performed. This field reflects the day that the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time before the test is performed. Some tests are listed as continuously performed, which means that assays are performed multiple times during the day.

Monday through Sunday

Report Available
The interval of time (receipt of sample at Mayo Clinic Laboratories to results available) taking into account standard setup days and weekends. The first day is the time that it typically takes for a result to be available. The last day is the time it might take, accounting for any necessary repeated testing.

Same day/1 to 3 days

Specimen Retention Time
Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded

7 days

Performing Laboratory Location
Indicates the location of the laboratory that performs the test


Several factors determine the fee charged to perform a test. Contact your U.S. or International Regional Manager for information about establishing a fee schedule or to learn more about resources to optimize test selection.

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Test Classification
Provides information regarding the medical device classification for laboratory test kits and reagents. Tests may be classified as cleared or approved by the US Food and Drug Administration (FDA) and used per manufacturer instructions, or as products that do not undergo full FDA review and approval, and are then labeled as an Analyte Specific Reagent (ASR) product.

This test has received Emergency Use Authorization (EUA) by the US Food and Drug Administration and is used per manufacturer’s instructions. Performance characteristics were verified by Mayo Clinic in a manner consistent with CLIA requirements.

CPT Code Information
Provides guidance in determining the appropriate Current Procedural Terminology (CPT) code(s) information for each test or profile. The listed CPT codes reflect Mayo Clinic Laboratories interpretation of CPT coding requirements. It is the responsibility of each laboratory to determine correct CPT codes to use for billing.

CPT codes are provided by the performing laboratory.


LOINC® Information
Provides guidance in determining the Logical Observation Identifiers Names and Codes (LOINC) values for the order and results codes of this test. LOINC values are provided by the performing laboratory.

Test Id Test Order Name Order LOINC Value
COVTA SARS-CoV-2 Nucleocapsid Total Ab, S 94762-2
Result Id Test Result Name Result LOINC Value
Applies only to results expressed in units of measure originally reported by the performing laboratory. These values do not apply to results that are converted to other units of measure.
COVTI SARS-CoV-2 Nucleocapsid Total Ab, S 94762-2
SRACE Patient's Race 72826-1
SETHN Patient's Ethnicity 69490-1

Test Setup Resources

Setup Files
Test setup information contains test file definition details to support order and result interfacing between Mayo Clinic Laboratories and your Laboratory Information System.

Excel | Pdf

Sample Reports
Normal and Abnormal sample reports are provided as references for report appearance.

Normal Reports | Abnormal Reports

SI Sample Reports
International System (SI) of Unit reports are provided for a limited number of tests. These reports are intended for international account use and are only available through MayoLINK accounts that have been defined to receive them.

SI Normal Reports | SI Abnormal Reports