Question reference: S5W-33595
- Asked by: Alexander Burnett, MSP for Aberdeenshire West, Scottish Conservative and Unionist Party
- Date lodged: 30 November 2020
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Current status: Answered by Jeane Freeman on 7 January 2021
Question
To ask the Scottish Government what the cycle threshold is for the polymerase chain reaction process being used for COVID-19 tests processed at (a) NHS and (b) Lighthouse Labs laboratories.
Answer
PCR tests are used to detect the presence of viral genetic material in a sample and the cycle thresholds (Ct) can be used as an indicator of the concentration of viral genetic material in a patient sample. A typical PCR assay will have a maximum of 40 thermal cycles.
Ct values are not directly comparable between assays and may not be reported by some PCR platforms in use. Individual laboratories will hold details of the Ct reached for each individual specimen who will have quality systems in place to ensure the veracity of the results.