Performance Characteristics of the Abbott Architect SARS-CoV-2 IgG Assay and Seroprevalence in Boise, Idaho

J Clin Microbiol. 2020 Jul 23;58(8):e00941-20. doi: 10.1128/JCM.00941-20. Print 2020 Jul 23.


Coronavirus disease 2019 (COVID-19), the novel respiratory illness caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is associated with severe morbidity and mortality. The rollout of diagnostic testing in the United States was slow, leading to numerous cases that were not tested for SARS-CoV-2 in February and March 2020 and necessitating the use of serological testing to determine past infections. Here, we evaluated the Abbott SARS-CoV-2 IgG test for detection of anti-SARS-CoV-2 IgG antibodies by testing 3 distinct patient populations. We tested 1,020 serum specimens collected prior to SARS-CoV-2 circulation in the United States and found one false positive, indicating a specificity of 99.90%. We tested 125 patients who tested reverse transcription-PCR (RT-PCR) positive for SARS-CoV-2 for whom 689 excess serum specimens were available and found that sensitivity reached 100% at day 17 after symptom onset and day 13 after PCR positivity. Alternative index value thresholds for positivity resulted in 100% sensitivity and 100% specificity in this cohort. We tested specimens from 4,856 individuals from Boise, ID, collected over 1 week in April 2020 as part of the Crush the Curve initiative and detected 87 positives for a positivity rate of 1.79%. These data demonstrate excellent analytical performance of the Abbott SARS-CoV-2 IgG test as well as the limited circulation of the virus in the western United States. We expect that the availability of high-quality serological testing will be a key tool in the fight against SARS-CoV-2.

Keywords: Abbott; COVID; COVID-19; Idaho; SARS; SARS-CoV-2; coronavirus; serology.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Antibodies, Viral / blood*
  • Betacoronavirus / immunology*
  • COVID-19
  • COVID-19 Testing
  • Clinical Laboratory Techniques / methods*
  • Coronavirus Infections / diagnosis
  • Coronavirus Infections / epidemiology*
  • Coronavirus Infections / immunology*
  • Female
  • Humans
  • Idaho / epidemiology
  • Immunoglobulin G / blood*
  • Male
  • Middle Aged
  • Pandemics
  • Pneumonia, Viral / epidemiology*
  • Pneumonia, Viral / immunology*
  • SARS-CoV-2
  • Sensitivity and Specificity
  • Seroepidemiologic Studies
  • Young Adult


  • Antibodies, Viral
  • Immunoglobulin G