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Comparative Study
. 2021 Feb;26(6):2002079.
doi: 10.2807/1560-7917.ES.2021.26.6.2002079.

Comparison and correlation of commercial SARS-CoV-2 real-time-PCR assays, Ireland, June 2020

Anne Carroll  1 , Eleanor McNamara  1
Affiliations
Comparative Study

Comparison and correlation of commercial SARS-CoV-2 real-time-PCR assays, Ireland, June 2020

Anne Carroll et al. Euro Surveill. 2021 Feb.

Abstract

We report the performance of a variety of commercially available SARS-CoV-2 PCR kits, used in several different sites across Ireland to determine if Ct values across platforms are comparable. We also investigate whether a Ct value, a surrogate for calculated viral loads in the absence of viral culture of > 34 can be used to exclude SARS-CoV-2 infection and its complications. We found a variation in Ct values from different assays for the same calculated viral load; this should be taken into consideration for result interpretation.

Keywords: Cycle threshold; RT-PCR; SARS-CoV-2.

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Conflict of interest statement

Conflict of interest: None declared.

Figures

Figure
Figure
Average Ct values at SARS-CoV-2 viral loads of 3log10 to 8log10 copies/mL, Ireland, June 2020 (n = 8 assays)a
See this image and copyright information in PMC

References

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    1. Health Service Executive (HSE) Health Protection Surveillance Centre. (HPSC). Guidance on the management of weak positive (high Ct value) PCR results in the setting of testing individuals for SARS-CoV-2 V1.2 22.12.2020. Ireland: HSE HPSC. Available from: https://www.hpsc.ie/a-z/respiratory/coronavirus/novelcoronavirus/guidanc...
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    1. Quality Control for Molecular Diagnostics (QCMD). [Accessed 11 Feb 2021]. Available from: http://www.qcmd.org/

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