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letter . 2021 Jul 29:hvab145. doi: 10.1093/clinchem/hvab145
Wide Variation in Cycle Threshold Values Cloud the Interpretation of COVID-19 Infectiousness
William Stokes
1,2,3,✉, Jamil Kanji
1,2,4,5, Jia Hu
6,7, Nathan Zelyas
1,2, Byron M Berenger
1,5
William Stokes
1Alberta Public Health Laboratory, Alberta Precision Laboratories, Alberta, Canada
2Department of Laboratory Medicine and Pathology, University of Alberta, Alberta, Canada
3Division of Infectious Diseases, Department of Medicine, University of Alberta, Edmonton, Alberta
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Jamil Kanji
1Alberta Public Health Laboratory, Alberta Precision Laboratories, Alberta, Canada
2Department of Laboratory Medicine and Pathology, University of Alberta, Alberta, Canada
4Division of Infectious Diseases, Department of Medicine, Cumming School of Medicine, University of Calgary, 3030 Hospital Drive NW, Calgary, AB, T2N 4W4, Canada
5Department of Pathology and Laboratory Medicine, University of Calgary, Calgary, Alberta, Canada
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Jia Hu
6Department of Community Health Sciences, University of Calgary, Calgary, Alberta, Canada
7Public Health, Alberta Health Services, Alberta, Canada
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Nathan Zelyas
1Alberta Public Health Laboratory, Alberta Precision Laboratories, Alberta, Canada
2Department of Laboratory Medicine and Pathology, University of Alberta, Alberta, Canada
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Byron M Berenger
1Alberta Public Health Laboratory, Alberta Precision Laboratories, Alberta, Canada
5Department of Pathology and Laboratory Medicine, University of Calgary, Calgary, Alberta, Canada
Find articles by Byron M Berenger
1Alberta Public Health Laboratory, Alberta Precision Laboratories, Alberta, Canada
2Department of Laboratory Medicine and Pathology, University of Alberta, Alberta, Canada
3Division of Infectious Diseases, Department of Medicine, University of Alberta, Edmonton, Alberta
4Division of Infectious Diseases, Department of Medicine, Cumming School of Medicine, University of Calgary, 3030 Hospital Drive NW, Calgary, AB, T2N 4W4, Canada
5Department of Pathology and Laboratory Medicine, University of Calgary, Calgary, Alberta, Canada
6Department of Community Health Sciences, University of Calgary, Calgary, Alberta, Canada
7Public Health, Alberta Health Services, Alberta, Canada
✉
Corresponding author William Stokes, Alberta Precision Laboratories, University of Alberta Hospital, 2B4.58 WMC, 8440-112 St NW, Edmonton, AB, T6G 2J2, Ph: 780-720-7025, Fax: 780-492-8050, William.Stokes@AlbertaPrecisionLabs.ca
Received 2021 May 27; Accepted 2021 Jul 13.
Keywords: Cycle Threshold (Ct), COVID-19, SARS-CoV-2, infectiousness, PCR
© 2021 American Association for Clinical Chemistry
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PMCID: PMC8344902 PMID: 34324000