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Comparative Study
. 2020 Jul:128:104428.
doi: 10.1016/j.jcv.2020.104428. Epub 2020 May 13.

Comparison of Cepheid Xpert Xpress and Abbott ID Now to Roche cobas for the Rapid Detection of SARS-CoV-2

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Comparative Study

Comparison of Cepheid Xpert Xpress and Abbott ID Now to Roche cobas for the Rapid Detection of SARS-CoV-2

Marie C Smithgall et al. J Clin Virol. 2020 Jul.

Abstract

Background: The SARS-CoV-2 pandemic has created an urgent and unprecedented need for rapid large-scale diagnostic testing to inform timely patient management. However, robust data are lacking on the relative performance of available rapid molecular tests across a full range of viral concentrations.

Objective: This study aimed to compare two recently-authorized rapid tests, Cepheid Xpert Xpress SARS-CoV-2 and Abbott ID Now SARS-CoV-2, to the Roche cobas SARS-CoV-2 assay for samples with low, medium, and high viral concentrations.

Study design: A total of 113 nasopharyngeal swabs from remnant patient samples were tested, including 88 positives spanning the full range of observed Ct values on the cobas assay.

Results: Compared to cobas, the overall positive agreement was 73.9% with ID Now and 98.9% with Xpert. Negative agreement was 100% and 92.0% for ID Now and Xpert, respectively. Both ID Now and Xpert showed 100% positive agreement for medium and high viral concentrations (Ct value <30). However, for Ct values >30, positive agreement was 34.3% for ID Now and 97.1% for Xpert.

Conclusions: While Xpert showed high agreement with cobas across a wide range of viral concentrations, this study highlights an important limitation of ID Now for specimens collected in viral or universal transport media with low viral concentrations. Further studies are needed to evaluate the performance of ID Now for direct swabs.

Keywords: COVID-19; Molecular Diagnostics; PCR; Point of Care; SARS-CoV-2.

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Figures

Fig. 1
Fig. 1
A: Frequency distribution of cycle threshold (Ct) values for positive patient samples by Roche cobas SARS-CoV-2 (blue), Cepheid Xpert Xpress SARS-CoV-2 (orange) and Abbott ID Now SARS-CoV-2(gray) assays. Roche cobas Target 1 (ORF1) Ct values were rounded to the nearest whole number. B: Frequency distribution of cycle threshold (Ct) values for positive patient samples by Roche cobas SARS-CoV-2 (blue), Cepheid Xpert Xpress SARS-CoV-2 (orange) and Abbott ID Now SARS-CoV-2(gray) assays. Roche cobas Target 1 (ORF1) Ct values were rounded to the nearest whole number.

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References

    1. Sheridan C. Coronavirus and the race to distribute reliable diagnostics. Nature Biotechnology. 2020;38:382–384. - PubMed
    1. Moran A., Beavis K.G., Matushek S.M. The Detection of SARS-CoV-2 using the Cepheid Xpert Xpress SARS-CoV-2 and Roche cobas SARS-CoV-2 Assays. J Clin Microbiol. 2020;(April) pii: JCM 00772-20. - PMC - PubMed
    1. Rhoads D., Cherian S., Roman K. Comparison of Abbott ID Now, Diasorin Simplexa, and CDC FDA EUA methods for the detection of SARS-CoV-2 from nasopharyngeal and nasal swabs from individuals diagnosed with COVID-19. J Clin Microbiol. 2020;(April) pii: JCM.00760-20. - PMC - PubMed
    1. Poljak M., Korva M., Gašper N.K. Clinical evaluation of the cobas SARS-CoV-2 test and a diagnostic platform switch during 48 hours in the midst of the COVID-19 pandemic. J Clin Microbiol. 2020;(April) JCM.00599-20. - PMC - PubMed
    1. Hogan C.A., Sahoo M.K., Huang C. Five-Minute-Point-of-Care Testing for SARS-CoV-2: Not There Yet. Journal of Clinical Virology. 2020 p. 104410. - PMC - PubMed

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