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COVID-19 antibody testing available

07 Jun 2020

Help us prioritize for health care workers

By: Karl Kamper, laboratory services director

Salem Health Laboratories is pleased to announce that we are now offering COVID-19 antibody testing. 

While this is available to the general public, please help prioritize testing for health care workers, including our community providers.

Test Information

  • SARS-COV-2 Antibody (IgG)
    • CPT Code: 86769 Antibody; severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (Coronavirus disease [COVID-19])
    • EPIC Order Number: LAB8341 SARS-COV2 ANTIBODY (IGG)
    • LAB Order Code: COVGG
  • Helpful Diagnosis Codes:
    • Z11.59: Encounter for screening for other viral diseases / Asymptomatic, no known exposure, results unknown or negative
    • Z03.818: Encounter for observation for suspected exposure to other biological agents ruled out / Possible exposure to COVID-19, infection ruled out
    • Z20.828: Contact with and (suspected) exposure to other viral communicable diseases / Contact with COVID-19, Suspected Exposure
  • Collection Information
    • Test Menu Update:
    • Preferred Specimen Collection: Gold Top-Serum Separator Tube; also acceptable: Red Top
    • Stability: Separate serum from cells ASAP or within 2 hours of collection.Transport refrigerated
    • Test Inquiry:Laboratory Services 503-814-5227(LABS)

Indications for use

The SARS-CoV-2 IgG test can help identify people with an adaptive immune response to SARS-CoV-2, indicating recent or prior infection. It is unknown for how long antibodies persist following infection and if the presence of antibodies confers protective immunity. Initial studies have shown that patients do not typically demonstrate detectable levels of IgG antibody to SARS-CoV-2 until at least 14 days after the onset of symptoms. The SARS­CoV-2 IgG assay should not be used to diagnose acute SARS-CoV-2 infection. Acute diagnosis testing should still be conducted using direct RT-PCR methods.

Intended population

The primary patient population that may benefit from testing for IgG antibodies includes those with potential exposure to SARS-CoV-2, but were unable to be tested at the time of symptom onset. This includes people assumed infected due to lack of testing capability early in the pandemic. Additionally, other individuals who have been in close contact with a patient with a known case of COVID-19 may benefit from testing. This includes family members, roommates, and other who cohabitate or live in close quarters with identified cases.  This group also includes health care workers, and others with an occupational risk for exposure to SARS-CoV-2.

Interpretation of results


A positive result means that a patient was most likely exposed to SARS-CoV-2 and has developed antibody directed against the virus. A positive result, however, does not inform a level of immunity. Studies are not yet available to demonstrate if antibody presence is capable of preventing repeat infection. Clinicians should be very direct in counseling patients that a positive response to SARS-CoV-2. IgG testing should not be used to inform future individual decisions about participation in social distancing, large gatherings, use of masks and other personal protective equipment, etc. in public or while performing job duties.


A negative result means one of the following:

  • Patients were most likely not infected with the SARS-Cov-2 virus.
  • Patients had a mild case or mild infection that did not result in sufficient production of SARS-CoV-2 IgG antibodies to be detectable by this test.
  • Patients had a specimen collected too soon after onset of symptoms to have developed detectable antibodies. In most cases, antibodies are typically detectable at 14 days after onset of symptoms. However, this is dependent on each individual, and may be different in patients with poor immune response or that are immunocompromised.

More information
The sensitivity of SARS-CoV-2 IgG early after infection is unknown. Negative results do not preclude acute SARS-CoV-2 infection. If acute infection is suspected, direct testing using an RT-PCR assay for SARS-CoV-2 is necessary.

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

Emergency use authorization

Salem Health Laboratories is performing the SARS-CoV-2 IgG assay under the Food and Drug Administration’s Emergency Use Authorization. This test was reviewed and authorized by the FDA.  Testing is being performed on an Abbott Architect i1000.

FAQ Sheet for Patients:

FAQ Sheet for Healthcare Providers: