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"Dead" Virus Cells Frequently Trigger "False Positives" In Most Common COVID-19 Test, New Study from Oxford University Finds

Viruses are not comprised of cells

That's because new research from the University of Oxford’s Center for Evidence-Based Medicine and the University of the West of England has found that the swab-based technique used for most COVID-19 testing is at risk of returning "false positives" since copies of the virus's RNA detected by the tests might simply be dead, inactive material from a weeks-old infection

PCR is a test for a specific sequence of nucleotides, not for intact virus. Strictly speaking, it’s not a false positive, but a misinterpretation of a positive result as meaning more than it does.

then utilize a "genetic photocopying" technique that allows scientists to magnify the small sample of genetic material collected, which they can then analyze for signs of viral RNA

PCR doesn’t indiscriminately amplify all the DNA/RNA present, leaving the scientists to “analyze for signs of viral RNA.” It amplifies only the viral RNA. It’s a present/not present test.

increasing the risk of this sample contamination

It’s not contamination, the test is working as designed. Again, it’s not a test for viable virions, just for the presence of viral genetic material, which doesn’t imply viable infective particles.

What the researchers here have effectively found is that these PCR tests just aren't sensitive enough to distinguish if the viral material is active and infectious, or dead and inert.

Ugh. The problem is the exact opposite- PCR is too sensitive for use as a test for presence of active infection.

This article raises a very real issue (positive PCR test does not automatically mean active infection), but I just want people here on FR to understand that the author of this article clearly does not understand the issue/technology in question and is giving false explanations. I just want people here to be properly informed.

For anyone wondering why I care /know: until a couple years ago I used to do PCR DNA/ RNA amplification and sequencing for a living.