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Test Code SARS Coronavirus 2 IgG and IgM Ab SARS COV-2 IgG IgM Antibody

Important Note


  • Serology should not be used to diagnose COVID-19 in the acute phase of illness, when RT-PCR is the recommended test. False negative serology test results can occur within the first 1 to 2 weeks of onset of symptoms/illness.
  • This test will detect only the IgG and IgM-class antibodies against SARS-CoV-2, the agent of COVID-19. 

Collection Instructions

Collect with normal blood draw procedures

Acceptable Specimens

Preferred: Green top Li-Hep tube

Also Acceptable: Gold Top Serum, K2 or K3 EDTA Purple top

Reference Ranges

Currently expected values are negative for IgG and IgM antibodies

Performance Information

Performed at UH Lab on the Roche e602, Monday through Saturday

Interpretation of Results

Nonreactive: A Negative test result does not rule out the possibility of acute infection with SARS-CoV-2 during the pre-seroconversion phase. Testing with SARS-CoV-2 by PCR should be performed to evaluate for active infection in symptomatic individuals. This test was ran run on the Roche Cobas system, results of assays from different manufacturers should not be used interchangeably.


Reactive: SARS-CoV-2 IgM/IgG antibodies 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 are diagnostic in the late phase of acuet infection when the sensitivity of SARS-CoV-2 RNA assay decreases. Protective immunity cannot be inferred based on these results alone. Infrequently, false-positive results may be due to prior infection with other human coronaviruses. The specificity of this Roche assay has been reported to be 99.8% . Results should not be used interchangeably with other manufacturers.