Your browser doesn't support javascript.
Show: 20 | 50 | 100
Results 1 - 3 de 3
Pathology ; 54:S26, 2022.
Article in English | ScienceDirect | ID: covidwho-1665348
Open Forum Infect Dis ; 8(7): ofab239, 2021 Jul.
Article in English | MEDLINE | ID: covidwho-1309620


BACKGROUND: Serological testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) complements nucleic acid tests for patient diagnosis and enables monitoring of population susceptibility to inform the coronavirus disease 2019 (COVID-19) pandemic response. It is important to understand the reliability of assays with different antigen or antibody targets to detect humoral immunity after SARS-CoV-2 infection and to understand how antibody (Ab) binding assays compare to those detecting neutralizing antibody (nAb), particularly as we move into the era of vaccines. METHODS: We evaluated the performance of 6 commercially available enzyme-linked immunosorbent assays (ELISAs), including a surrogate virus neutralization test (sVNT), for detection of SARS-CoV-2 immunoglobulins (IgA, IgM, IgG), total or nAb. A result subset was compared with a cell culture-based microneutralization (MN) assay. We tested sera from patients with prior reverse transcription polymerase chain reaction-confirmed SARS-CoV-2 infection, prepandemic sera, and potential cross-reactive sera from patients with other non-COVID-19 acute infections. RESULTS: For sera collected >14 days post-symptom onset, the assay achieving the highest sensitivity was the Wantai total Ab at 100% (95% CI, 94.6%-100%), followed by 93.1% for Euroimmun NCP-IgG, 93.1% for GenScript sVNT, 90.3% for Euroimmun S1-IgG, 88.9% for Euroimmun S1-IgA, and 83.3% for Wantai IgM. Specificity for the best-performing assay was 99.5% for the Wantai total Ab, and for the lowest-performing assay it was 97.1% for sVNT (as per the Instructions for Use [IFU]). The Wantai Total Ab had the best agreement with MN at 98% followed by Euroimmun S1-IgA, Euro NCP-IgG, and sVNT (as per IFU) with 97%, 97% and 95%, respectively; Wantai IgM had the poorest agreement at 93%. CONCLUSIONS: Performance characteristics of the SARS-CoV-2 serology assays detecting different antibody types are consistent with those found in previously published reports. Evaluation of the surrogate virus neutralization test in comparison to the Ab binding assays and a cell culture-based neutralization assay showed good result correlation between all assays. However, correlation between the cell-based neutralization test and some assays detecting Ab's not specifically involved in neutralization was higher than with the sVNT. This study demonstrates the reliability of different assays to detect the humoral immune response following SARS-CoV-2 infection, which can be used to optimize serological test algorithms for assessing antibody responses post-SARS-CoV-2 infection or vaccination.

J Infect Dis ; 222(8): 1280-1288, 2020 09 14.
Article in English | MEDLINE | ID: covidwho-695351


BACKGROUND: Robust serological assays are essential for long-term control of the COVID-19 pandemic. Many recently released point-of-care (PoCT) serological assays have been distributed with little premarket validation. METHODS: Performance characteristics for 5 PoCT lateral flow devices approved for use in Australia were compared to a commercial enzyme immunoassay (ELISA) and a recently described novel surrogate virus neutralization test (sVNT). RESULTS: Sensitivities for PoCT ranged from 51.8% (95% confidence interval [CI], 43.1%-60.4%) to 67.9% (95% CI, 59.4%-75.6%), and specificities from 95.6% (95% CI, 89.2%-98.8%) to 100.0% (95% CI, 96.1%-100.0%). ELISA sensitivity for IgA or IgG detection was 67.9% (95% CI, 59.4%-75.6%), increasing to 93.8% (95% CI, 85.0%-98.3%) for samples >14 days post symptom onset. sVNT sensitivity was 60.9% (95% CI, 53.2%-68.4%), rising to 91.2% (95% CI, 81.8%-96.7%) for samples >14 days post symptom onset, with specificity 94.4% (95% CI, 89.2%-97.5%). CONCLUSIONS: Performance characteristics for COVID-19 serological assays were generally lower than those reported by manufacturers. Timing of specimen collection relative to onset of illness or infection is crucial in reporting of performance characteristics for COVID-19 serological assays. The optimal algorithm for implementing serological testing for COVID-19 remains to be determined, particularly in low-prevalence settings.

Coronavirus Infections/blood , Pneumonia, Viral/blood , Algorithms , Antibodies, Viral/blood , Australia/epidemiology , Betacoronavirus/isolation & purification , COVID-19 , COVID-19 Testing , Clinical Laboratory Techniques , Coronavirus Infections/diagnosis , Coronavirus Infections/epidemiology , Enzyme-Linked Immunosorbent Assay , Humans , Immunoglobulin A/blood , Immunoglobulin G/blood , Neutralization Tests/methods , Pandemics , Pneumonia, Viral/diagnosis , Pneumonia, Viral/epidemiology , Prevalence , Reverse Transcriptase Polymerase Chain Reaction/methods , SARS-CoV-2 , Serologic Tests/methods , Serologic Tests/standards