In:
PLOS ONE, Public Library of Science (PLoS), Vol. 17, No. 1 ( 2022-1-20), p. e0262656-
Abstract:
SARS-CoV-2, the cause of COVID-19, requires reliable diagnostic methods to track the circulation of this virus. Following the development of RT-qPCR methods to meet this diagnostic need in January 2020, it became clear from interlaboratory studies that the reported Ct values obtained for the different laboratories showed high variability. Despite this the Ct values were explored as a quantitative cut off to aid clinical decisions based on viral load. Consequently, there was a need to introduce standards to support estimation of SARS-CoV-2 viral load in diagnostic specimens. In a collaborative study, INSTAND established two reference materials (RMs) containing heat-inactivated SARS-CoV-2 with SARS-CoV-2 RNA loads of ~10 7 copies/mL (RM 1) and ~10 6 copies/mL (RM 2), respectively. Quantification was performed by RT-qPCR using synthetic SARS-CoV-2 RNA standards and digital PCR. Between November 2020 and February 2021, German laboratories were invited to use the two RMs to anchor their Ct values measured in routine diagnostic specimens, with the Ct values of the two RMs. A total of 305 laboratories in Germany were supplied with RM 1 and RM 2. The laboratories were requested to report their measured Ct values together with details on the PCR method they used to INSTAND. This resultant 1,109 data sets were differentiated by test system and targeted gene region. Our findings demonstrate that an indispensable prerequisite for linking Ct values to SARS-CoV-2 viral loads is that they are treated as being unique to an individual laboratory. For this reason, clinical guidance based on viral loads should not cite Ct values. The RMs described were a suitable tool to determine the specific laboratory Ct for a given viral load. Furthermore, as Ct values can also vary between runs when using the same instrument, such RMs could be used as run controls to ensure reproducibility of the quantitative measurements.
Type of Medium:
Online Resource
ISSN:
1932-6203
DOI:
10.1371/journal.pone.0262656
DOI:
10.1371/journal.pone.0262656.g001
DOI:
10.1371/journal.pone.0262656.g002
DOI:
10.1371/journal.pone.0262656.g003
DOI:
10.1371/journal.pone.0262656.g004
DOI:
10.1371/journal.pone.0262656.g005
DOI:
10.1371/journal.pone.0262656.g006
DOI:
10.1371/journal.pone.0262656.g007
DOI:
10.1371/journal.pone.0262656.g008
DOI:
10.1371/journal.pone.0262656.g009
DOI:
10.1371/journal.pone.0262656.g010
DOI:
10.1371/journal.pone.0262656.t001
DOI:
10.1371/journal.pone.0262656.t002
DOI:
10.1371/journal.pone.0262656.t003
DOI:
10.1371/journal.pone.0262656.t004
DOI:
10.1371/journal.pone.0262656.t005
DOI:
10.1371/journal.pone.0262656.s001
DOI:
10.1371/journal.pone.0262656.s002
DOI:
10.1371/journal.pone.0262656.s003
DOI:
10.1371/journal.pone.0262656.s004
DOI:
10.1371/journal.pone.0262656.s005
DOI:
10.1371/journal.pone.0262656.s006
DOI:
10.1371/journal.pone.0262656.s007
DOI:
10.1371/journal.pone.0262656.s008
DOI:
10.1371/journal.pone.0262656.s009
Language:
English
Publisher:
Public Library of Science (PLoS)
Publication Date:
2022
detail.hit.zdb_id:
2267670-3
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