Data, even from a bad test, if it is consistently "bad", might be useful, but to take absolute values from a mass testing project in the way that has been done, and ignore the caveats, without even exploring the operational false positive rate, seems unwise.
Having said that, even these tests, which must be considered, at best, unreliable, are showing a decline in positive results, which may or may not be significant.
Altogether though, wholly unsatisfactory.
rtPCR is an incredibly useful diagnostic tool and is very good at detecting specific *exposure* to COVID.
We can't tell who is or isnt infected which is a problem but overall up/down trends can be worked out from exposure.
And generally the higher the viral load the stronger it'll react to PCR at a lower number of cycles.
That part is fine, its useful. Where its NOT useful is used as a one off single test to gauge *infection* which is (i) what the government's OWN briefing paper say not to do and (ii) exactly what we, and most of the world, is doing.
Data can if combined with other methods can be used to give a useful indication of if an individual is infected....but we dont do it that way. Which is the problem.
It sounds rather like that old joke, splatt:
Not strictly true, it can show us if someone has been *exposed*.
If they're exposed there's a chance they're infected, therefore we can ask them to isolate to avoid it spreading further.
Thats why the PCR tests are *supposed* to be combined with symptoms - you have 2 independent factors suggesting infection. The problem is plenty of surveillance testing is done without symptoms which means just 1 potential diagnostic with no independent verification.
What we also should have done is cultured virus at various cTs from each manufacturers test to determine a minimal and accepted cT for that particular assay and test.
But we didn't do that either. If we had, it would be a LOT more useful.
Basically we're using tests always run at full sensitivity with no calibration against what they're testing FOR. Which is criminal scientifically. An undergraduate would get binned immediately for such shambolic experimental design.
An undergraduate would get binned immediately for such shambolic experimental design.
There is such an offence as Gross Negligence.
And these fellows are leaving a lot of evidence lying around, gross negligence is plain negligence with the addition of a vituperative epithet .Perhaps we can nail Mr. Hancock and SAGE when this dies down and the public inquiry gets going.
Interesting to note that we have Patrick Vallance as our top state scientist and the USA has Moncef Slaoui heading up the US vaccination programme. Vallance was Slaoui’s successor as head of R&D at GSK.
