E Tuaillon1, K Bolloré2, A Pisoni3, S Debiesse2, C Renault2, S Marie4, S Groc4, C Niels4, N Pansu4, A M Dupuy4, D Morquin4, V Foulongne3, A Bourdin4, V Le Moing4, P Van de Perre3. 1. Pathogenesis and Control of Chronic Infections, University of Montpellier, INSERM, EFS; CHU Montpellier, Montpellier, France. Electronic address: e-tuaillon@chu-montpellier.fr. 2. Pathogenesis and Control of Chronic Infections, University of Montpellier, INSERM, EFS, Montpellier, France. 3. Pathogenesis and Control of Chronic Infections, University of Montpellier, INSERM, EFS; CHU Montpellier, Montpellier, France. 4. Montpellier University Hospital, Montpellier, France.
Abstract
OBJECTIVES: SARS-CoV-2 antibody assays are needed for serological surveys and as a complement to molecular tests to confirm COVID-19. However, the kinetics of the humoral response against SARS-CoV-2 remains poorly described and relies on the performance of the different serological tests. METHODS: In this study, we evaluated the performance of six CE-marked point-of-care tests (POC) and three ELISA assays for the diagnosis of COVID-19 by exploring seroconversions in hospitalized patients who tested positive for SARS-CoV-2 RNA. RESULTS: Both the ELISA and POC tests were able to detect SARS-CoV-2 antibodies in at least half of the samples collected seven days or more after the onset of symptoms. After 15 days, the rate of detection rose to over 80% but without reaching 100%, irrespective of the test used. More than 90% of the samples collected after 15 days tested positive using the iSIA and Accu-Tell® POC tests and the ID.Vet IgG ELISA assay. Seroconversion was observed 5 to 12 days after the onset of symptoms. Three assays suffer from a specificity below 90% (EUROIMMUN IgG and IgA, UNscience, Zhuhai Livzon). CONCLUSIONS: The second week of COVID-19 seems to be the best period for assessing the sensitivity of commercial serological assays. To achieve an early diagnosis of COVID-19 based on antibody detection, a dual challenge must be met: the immunodiagnostic window period must be shortened and an optimal specificity must be conserved.
OBJECTIVES:SARS-CoV-2 antibody assays are needed for serological surveys and as a complement to molecular tests to confirm COVID-19. However, the kinetics of the humoral response against SARS-CoV-2 remains poorly described and relies on the performance of the different serological tests. METHODS: In this study, we evaluated the performance of six CE-marked point-of-care tests (POC) and three ELISA assays for the diagnosis of COVID-19 by exploring seroconversions in hospitalized patients who tested positive for SARS-CoV-2 RNA. RESULTS: Both the ELISA and POC tests were able to detect SARS-CoV-2 antibodies in at least half of the samples collected seven days or more after the onset of symptoms. After 15 days, the rate of detection rose to over 80% but without reaching 100%, irrespective of the test used. More than 90% of the samples collected after 15 days tested positive using the iSIA and Accu-Tell® POC tests and the ID.Vet IgG ELISA assay. Seroconversion was observed 5 to 12 days after the onset of symptoms. Three assays suffer from a specificity below 90% (EUROIMMUN IgG and IgA, UNscience, Zhuhai Livzon). CONCLUSIONS: The second week of COVID-19 seems to be the best period for assessing the sensitivity of commercial serological assays. To achieve an early diagnosis of COVID-19 based on antibody detection, a dual challenge must be met: the immunodiagnostic window period must be shortened and an optimal specificity must be conserved.
Authors: Fergus Hamilton; Peter Muir; Marie Attwood; Alan Noela Barry Vipond; Richard Hopes; Ed Moran; Nick Maskell; Deborah Warwick; Mahableshwar Albur; Jonathan Turner; Alasdair MacGowan; David Arnold Journal: J Infect Date: 2020-07-30 Impact factor: 6.072
Authors: Antonio La Marca; Martina Capuzzo; Tiziana Paglia; Laura Roli; Tommaso Trenti; Scott M Nelson Journal: Reprod Biomed Online Date: 2020-06-14 Impact factor: 3.828