I am sorry but this doctor has been called out multiple times for making misleading claims. Some of what she says is "technically" factually correct but it is presented in such a way to illicit a response that the PCR test is a non-viable screening tool (qPCR is a tool in the diagnostic chain, I want to emphasize that because she is acting like it is solely used which it isn't.) She also vastly overestimates the sensitivity of PCR tests. Yes a single DNA fragment could, if left for long enough, produce a positive result in a PCR test however it would take weeks for a PCR test to produce viable results by which point its also possible that contamination occurred and corrupted the test, which is why we only run the tests for around 24 hours (think of PCR tests as a DNA photocopier that only photocopies a specific type of image... if there is a stack of 100,000,000 photos that it has to check and only 1 of them is the correct image that it can photocopy and it takes 1 day to check all 100,000,000 then at the end of that day you will have 2 photos... However if 10,000,000 of that 100,000,000 are the right photos then you will end up with 20,000,000 photos which is far easier to check if you made copies). Other things she says are also flat out incorrect.