Users of RT-PCR reagents should read the IFU carefully to determine if manual adjustment of the PCR positivity threshold is necessary to account for any background noise which may lead to a specimen with a high cycle threshold (Ct) value result being interpreted as a positive result.

https://www.theburningplatform.com/2020/12/19/who-finally-admits-pcr-tests-create-false-positives/

Up until COVID hit in 2020, neither WHO nor the CDC had ever considered a single positive PCR test sufficient for diagnosing viral infection.

https://redstate.com/michael_thau/2021/01/20/total-coincidence-alert-who-issues-new-c19-guidelines-requiring-2nd-test-for-symptom-less-on-day-biden-takes-office-n313400

PCR positive is no longer = Covid. You are not Covid now unless you get a second test to confirm it, and are presenting clinical symptoms. We shall see what the net impact of this indeed is.

Released 20/21 Jan 2020https://t.co/giAYWjQFDB pic.twitter.com/axKemwS2Sx

— Ethical Skeptic ☀ (@EthicalSkeptic) January 20, 2021