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Volume 29, Number 10—October 2023
Research

Cycle Threshold Values as Indication of Increasing SARS-CoV-2 New Variants, England, 2020–2022

Rebecca E. HarrisonComments to Author , Ahmed Hamada, Nujcharee Haswell, Aigul Groves, Karina-Doris Vihta, Kerry Cella, Sarah Garner, Ann Sarah Walker, and Anna C. Seale
Author affiliations: United Kingdom Health Security Agency, London, UK (R.E. Harrison, A. Hamada, N. Haswell, A. Groves, K. Cella, S. Garner, A.C. Seale); University of Oxford, Oxford, UK (K.-D. Vihta, A.S. Walker); Warwick Medical School, University of Warwick, Coventry, UK (A.C. Seale); London School of Hygiene & Tropical Medicine, London (A.C. Seale)

Main Article

Figure 1

Weekly Taqpath reverse transcription quantitative PCR (27) gene detection (S+/S−) in SARS-CoV-2 infections, England, August 31, 2020–January 31, 2022. The chart excludes cycle threshold (Ct) values >30 for S− because when Ct >30, the S− may be caused by a sample of low quality or with low viral load rather than a reliable S− signal. Test results for which only 1 gene is detected are excluded. S, spike; S+, presence of S gene; S−, absence of S gene.

Figure 1. Weekly Taqpath reverse transcription quantitative PCR (27) gene detection (S+/S−) in SARS-CoV-2 infections, England, August 31, 2020–January 31, 2022. The chart excludes cycle threshold (Ct) values >30 for S− because when Ct >30, the S− may be caused by a sample of low quality or with low viral load rather than a reliable S− signal. Test results for which only 1 gene is detected are excluded. S, spike; S+, presence of S gene; S−, absence of S gene.

Main Article

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Page created: August 16, 2023
Page updated: September 20, 2023
Page reviewed: September 20, 2023
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