Detection of SARS-CoV-2 antibodies is insufficient for the diagnosis of active or cured COVID-19

• Published in: Scientific reports Vol. 10; no. 1; p. 19893
• Main Authors: Escribano, Pilar, Álvarez-Uría, Ana, Alonso, Roberto, Catalán, Pilar, Alcalá, Luis, Muñoz, Patricia, Guinea, Jesús
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 16.11.2020; Nature Publishing Group
• Subjects: 631/326/2521; 692/308/53/2421; Aged; Antibodies; Coronaviruses; COVID-19; COVID-19 - blood; COVID-19 - diagnosis; COVID-19 Serological Testing - standards; Diagnosis; Emergency medical care; Female; Humanities and Social Sciences; Humans; Immunoglobulin G; Immunoglobulin M; Male; Middle Aged; multidisciplinary; Pandemics; Patients; Reagent Kits, Diagnostic - standards; Science; Science (multidisciplinary); Sensitivity and Specificity; Severe acute respiratory syndrome coronavirus 2
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-020-76914-5

We assessed the performance of Abbott's SARS-CoV-2 IgG assay and the Panbio TM COVID-19 IgG/IgM rapid test device for the diagnosis of either active or cured COVID-19. Three cohorts of patients were chosen. Cohort 1, patients (n = 65) who attended the emergency department on March 30, 2020 with clinical suspicion of active COVID-19 (n = 56 with proven/probable COVID-19). Cohort 2, hospital workers (n = 92) who had either been (n = 40) or not (n = 52) diagnosed with proven/probable COVID-19 and were asymptomatic at the time of the sampling. Cohort 3, patients (n = 38) cared at the hospital before the start of the COVID-19 pandemic. Detection of serum antibodies was done using Abbott´s SARS-CoV-2 IgG assay and the Panbio TM COVID-19 IgG/IgM device. Both methods showed 98% agreement for IgG detection. No antibodies were detected in the 38 samples from hospitalized pre-COVID subjects. The diagnostic performance of IgGs detected by Abbott´s SARS-CoV-2 assay in Cohorts 1/2 was: sensitivity (60.7%/75%) and specificity (100%/84.6%). The diagnostic performance of IgM by Panbio TM COVID-19 in Cohorts 1/2 was: sensitivity (16%/17.5%) and specificity (100%/98.1%). We show that IgG detection alone is insufficient for the diagnosis of active or cured COVID-19. IgM detection has a limited diagnostic value.