Figure 2.

Schematic representation of RT-PCR and digital PCR procedures used to detect SARS-CoV-2. In both assays, appropriate specimens are collected and viral RNA is extracted. In RT-PCR, the relative or absolute concentration of the target of interest is assessed by measuring the fluorescent signal that shows the amplification in each cycle. In digital PCR, the absolute concentration of the target nucleic acid is determined based on the number of partitions that are either positive or negative for amplification based on fluorescent signals.