A Portuguese appeals court has ruled that PCR tests are unreliable and that it is unlawful to quarantine people based solely on a PCR test.
The court stated, the test’s reliability depends on the number of cycles used and the viral load present. Citing Jaafar et al. 2020, the court concludes that:
“if someone is tested by PCR as positive when a threshold of 35 cycles or higher is used (as is the rule in most laboratories in Europe and the US), the probability that said person is infected is less than 3%, and the probability that said result is a false positive is 97%.”
The court further notes that the cycle threshold used for the PCR tests currently being made in Portugal is unknown.