That’s a fair point.
Lingering in the back of my head is that, released under EUA, the existing PCR was developed absent the isolated COVID virus. Teams were still working to “capture” the bug in isolation as the test was being released for use. I don’t believe they’d even got a complete “spike” protein isolated, yet.
About two weeks ago, someone I was listening to read off at least a partial roster of the various bits that were put in the PCR test stew; I couldn’t reproduce the list, but it did strike me at the time to wonder Howe they thought they could be accurate building it without any pieces of the actual bug.
They were working without a direct sample of SARS-CoV-2, but they did have the complete nucleotide sequence in hand. So the test was designed based on that. You can then test it by inserting the specific sequence you’re testing with into another virus and do your testing with that. It’s easy enough to do with modern technology.
The risk would then be if the Chinese lied about the nucleotide sequence. They certainly lied about plenty of other things. Thankfully, what was provided to the world was accurate to the original Wuhan virus. SARS-CoV-2 was then isolated and sequenced, and that’s been done many thousands of times since then around the country and around the world. That’s how you track the emergence and progress of variants: you sequence the whole sample taken from a positive specimen and see if there are any changes from your reference.
The real disaster is that CDC opted not to use the already available and working WHO test for SARS-CoV-2. I still haven’t seen anything that tells me the WHO assay isn’t perfectly functional. CDC spent weeks mucking about creating their own and not allowing anyone in the US to use the WHO tests. They then managed to screw that up to by shipping the first batches of test kits with contaminated components. The US lost a solid month of being able to track and contain this bug while CDC sat around doing nothing of value. It’s difficult to say how many Americans died because CDC was incompetent with the test kits, but I think a very conservative estimate would put it in the thousands.