Florida mandates testing labs report PCR “cycle threshold values”

On December 3, 2020, the US state of Florida, headed by Governor Ron deSantis, mandated that all COVID-19 testing labs to report the “cycle threshold values” for every PCR test they perform – in an attempt to rule out the high rate of false positive results. [1, 2]

Governor deSantis is guided by Florida’s Surgeon General Dr Joseph Ladapo, who is trained in public health and is following the scientific evidence.

Reporting cycle number (Ct value) for a quantitative PCR (qPCR) diagnostic test, that is the number of amplifications needed to return a “fluorescence” reading for the sample in an automated thermal cycler, was a standard procedure for pathology labs prior to COVID-19 pandemic.  The lower the Ct number the more confident a clinician can be they got their diagnosis is correct.  For other diseases such as pertussis ≥ 35 is classified as “indeterminate”, and tests should not be used alone.