“on its own”

Trust the Evidence- The SARS-CoV-2 transmission riddle – Part 3

Learning point: The lower the Ct, the higher the chance of infectivity: this is due to the nature of PCR which amplifies the target viral components through a series of cycles. The higher the concentration of viral components in the sample, the sooner the amplifications stop and the lower the number of cycles needed to identify the component.

However, those people with pre-existing pathologies or whose immune system is partly compromised may continue excreting infectious particles for a very long time, with a Ct which dips when they become infectious and may go up again when their defences are successfully fighting the virus.

For the vast majority of healthy people, though, peak infectiousness lasts just a few days before the infection wanes. Sometimes it precedes the onset of symptoms, or there are no symptoms at all, or the symptoms are minimal. When their immune systems have successfully neutralized the virus, they may continue to expel fragments for weeks or even months. These are picked up by PCR, but their good health and high Ct should testify to their recovered status – if you record the details.

Herein lies the insanity of mass screening with PCR in the absence of sufficient information and detailed follow-up of each person tested. It explains why so many people still test “positive” even though they are no longer infectious.