转：拜登就职一个小时后，世卫宣布，高扩增率的PCR测试会导致大量的假阳性。
按照世卫新的指南操作，美国的确诊数量会显著下降了。
...The notice was released only one hour after President Joe Biden was sworn into office, leading some observers to question the timing of the release.
The new guidance states that the "WHO reminds IVD users that disease prevalence alters the predictive value of test results; as disease prevalence decreases, the risk of false positive increases (2)." The notice reads: "This means that the probability that a person who has a positive result (SARS-CoV-2 detected) is truly infected with SARS-CoV-2 decreases as prevalence decreases, irrespective of the claimed specificity."
If the PCR tests are resulting in false-positives, and that information is now used to mitigate the large positivity numbers, the number of case counts will begin to drop.
https://thepostmillennial.com/who-warns-that-pcr-covid-tests-are-more-likely-to-give-false-positives
