In a CDC document titled, “Coronavirus Disease 2019 (COVID-19) 2020 Interim Case Definition, Approved April 5, 2020,” under the section, “Laboratory Criteria,” we have this:
“Detection of severe acute respiratory syndrome coronavirus 2 ribonucleic acid (SARS-CoV-2 RNA) in a clinical specimen using a molecular amplification detection test.”
The test referred to is the PCR. And as you can plainly see, it is detecting, not the virus itself, but a piece of RNA.
