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forget all the revelations about FALSE POSITIVES. Cambridge University/BBC/ABC Australia are broadcasting the following (in Australia today). note how small the “studies” are, not to mention other rubbish:

8 Sept: The Naked Scientists: How can you catch all the false negatives?
(broadcast on BBC and ABC Australia)
Interview with Ravi Gupta, University of Cambridge
One big problem when testing people for COVID-19 is false negative test results. This is where a person is tested for coronavirus infection and told they are negative when in reality they really are infected: one study found that this might be the case in more than half of patients...

But there are ways of making sure that these people don’t slip through the net. Adam Murphy spoke to Ravi Gupta, form the University of Cambridge, who has been testing one of them…

Ravi: So this study does not call into question what’s happening in screening strategies. So if you screen negative, then you’re not infectious. So I really want to make sure that people don’t come away from this thinking that a negative test out in the community means you could still have COVID. Our study was really looking at hospitalised patients where they have virus production lower down towards their lungs...
And when we put the antibody test together with the swab test that looks for genetic material, we were able to come up with a highly sensitive and specific test for patients coming to hospital, so that we could get up to a hundred percent diagnoses.

Adam - Is that what you can get up to then, 100%?

Ravi - Yes, so in this small study, it was a relatively small number. It was only about 50 patients that we were able to do this in, because you needed to have stored serum, you needed to have a diagnosis at the front door and you needed to have had the correct swab taken...

Adam - And then what about the other side? False positives. Does this become a problem with this method?

Ravi - The nose and throat swab for genetic material of the virus, what we call PCR, has been shown to be very highly sensitive, with a very low false positive rate. You really don’t get many false positives with that. But on the other hand, the antibody tests have a reputation for having a higher false positivity rate. So coming up with a positive, when the patient actually is negative. To address that, we looked at something like between 120, 150 patients with the antibody test. And we found only, I think, well, between zero and one false positive, so this was actually better than we expected. So the tests actually performed very well. The finger prick antibody tests that people think are not doing so well, the selected ones performed very well in our hands. And that’s the key thing. There are good tests and bad tests depending on the manufacturer. So if you choose the right test, you really can get high levels of accuracy...
https://www.thenakedscientists.com/articles/interviews/improving-covid-testing