tetano
Editor, Senior Moderator
Infect Dis Ther
. 2021 Aug 9.
doi: 10.1007/s40121-021-00510-x. Online ahead of print.
Multicenter Evaluation of a Fully Automated High-Throughput SARS-CoV-2 Antigen Immunoassay
Dominik Nörz[SUP] #[/SUP][SUP] 1 [/SUP], Flaminia Olearo[SUP] #[/SUP][SUP] 1 [/SUP], Stojan Perisic[SUP] 2 [/SUP], Matthias F Bauer[SUP] 3 [/SUP], Elena Riester[SUP] 4 [/SUP], Tanja Schneider[SUP] 5 [/SUP], Kathrin Schönfeld[SUP] 5 [/SUP], Tina Laengin[SUP] 5 [/SUP], Marc Lütgehetmann[SUP] 6 [/SUP]
Affiliations
Abstract
Introduction: Molecular testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to suffer from delays and shortages. Antigen tests have recently emerged as a viable alternative to detect patients with high viral loads, associated with elevated risk of transmission. While rapid lateral flow tests greatly improved accessibility of SARS-CoV-2 detection in critical areas, their manual nature limits scalability and suitability for large-scale testing schemes. The Elecsys[SUP]®[/SUP] SARS-CoV-2 Antigen assay allows antigen immunoassays to be carried out on fully automated high-throughput serology platforms.
Methods: A total of 3139 nasopharyngeal and oropharyngeal swabs were collected at 3 different testing sites in Germany. Swab samples were pre-characterized by reverse transcription real-time polymerase chain reaction (RT-qPCR) and consecutively subjected to the antigen immunoassay on either the cobas e 411 or cobas e 801 analyzer.
Results: Of the tested respiratory samples, 392 were PCR positive for SARS-CoV-2 RNA. Median concentration was 2.95 × 10[SUP]4[/SUP] (interquartile range [IQR] 5.1 × 10[SUP]2[/SUP]-3.5 × 10[SUP]6[/SUP]) copies/ml. Overall sensitivity and specificity of the antigen immunoassay were 60.2% (95% confidence interval [CI] 55.2-65.1) and 99.9% (95% CI 99.6-100.0), respectively. A 93.7% (95% CI 89.7-96.5) sensitivity was achieved at a viral RNA concentration ≥ 10[SUP]4[/SUP] copies/ml (~ cycle threshold [C[SUB]t[/SUB]] value < 29.9).
Conclusion: The Elecsys SARS-CoV-2 Antigen assay reliably detected patient samples with viral loads ≥ 10,000 copies/ml. It thus represents a viable high-throughput alternative for screening of patients or in situations where PCR testing is not readily available.
Keywords: Antigen immunoassay; High-throughput platform; SARS-CoV-2.
. 2021 Aug 9.
doi: 10.1007/s40121-021-00510-x. Online ahead of print.
Multicenter Evaluation of a Fully Automated High-Throughput SARS-CoV-2 Antigen Immunoassay
Dominik Nörz[SUP] #[/SUP][SUP] 1 [/SUP], Flaminia Olearo[SUP] #[/SUP][SUP] 1 [/SUP], Stojan Perisic[SUP] 2 [/SUP], Matthias F Bauer[SUP] 3 [/SUP], Elena Riester[SUP] 4 [/SUP], Tanja Schneider[SUP] 5 [/SUP], Kathrin Schönfeld[SUP] 5 [/SUP], Tina Laengin[SUP] 5 [/SUP], Marc Lütgehetmann[SUP] 6 [/SUP]
Affiliations
- PMID: 34370269
- DOI: 10.1007/s40121-021-00510-x
Abstract
Introduction: Molecular testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to suffer from delays and shortages. Antigen tests have recently emerged as a viable alternative to detect patients with high viral loads, associated with elevated risk of transmission. While rapid lateral flow tests greatly improved accessibility of SARS-CoV-2 detection in critical areas, their manual nature limits scalability and suitability for large-scale testing schemes. The Elecsys[SUP]®[/SUP] SARS-CoV-2 Antigen assay allows antigen immunoassays to be carried out on fully automated high-throughput serology platforms.
Methods: A total of 3139 nasopharyngeal and oropharyngeal swabs were collected at 3 different testing sites in Germany. Swab samples were pre-characterized by reverse transcription real-time polymerase chain reaction (RT-qPCR) and consecutively subjected to the antigen immunoassay on either the cobas e 411 or cobas e 801 analyzer.
Results: Of the tested respiratory samples, 392 were PCR positive for SARS-CoV-2 RNA. Median concentration was 2.95 × 10[SUP]4[/SUP] (interquartile range [IQR] 5.1 × 10[SUP]2[/SUP]-3.5 × 10[SUP]6[/SUP]) copies/ml. Overall sensitivity and specificity of the antigen immunoassay were 60.2% (95% confidence interval [CI] 55.2-65.1) and 99.9% (95% CI 99.6-100.0), respectively. A 93.7% (95% CI 89.7-96.5) sensitivity was achieved at a viral RNA concentration ≥ 10[SUP]4[/SUP] copies/ml (~ cycle threshold [C[SUB]t[/SUB]] value < 29.9).
Conclusion: The Elecsys SARS-CoV-2 Antigen assay reliably detected patient samples with viral loads ≥ 10,000 copies/ml. It thus represents a viable high-throughput alternative for screening of patients or in situations where PCR testing is not readily available.
Keywords: Antigen immunoassay; High-throughput platform; SARS-CoV-2.