Originally Posted by
Excargodog
That’s all well and good but as the man said, “Don’t compare me to the almighty, compare me to the alternative.”
The alternative currently is testing for viral particle fragments. It is a test that was fielded and mass produced with great difficulty over a few months. Initial batches of tests had to be recalled because contamination of one of the reagents by the control positive material, giving positive tests even with control blanks. Other tests from overseas sources (mostly China) were returned by the U.K. and Iran because they simply did not work.
when it DOES work it works only on the covid-19 in a narrow timeframe of the illness. Test too soon - it’s negative. Test too late - it is again negative. We KNOW it has a low predictive value positive AND negative in actual practice.
That's the usual with viral replicant test. In the early days of HIV we didn't test for the virus we tested for the antibodies. We still do but now able to test for viral load. Now HIV patients are classified as undetected with treatment, yet the virus may still be present and without treatment may/ will be detectable again.
The current rapid PCR test is still cumbersome. I have 1000s of hours driving a PCR. The whole contaminated reagent thing... fancy news to say... in reality, the USA is a fragmented system of clinical labs, small and large, some universities and the CDC which is actually not that large and is a research agency not a large scale clinical testing facility. Unfortunately there was no guidance in the beginning on who is to do what and the CDC was forced to produce a commercial test kit, something it never does with a relatively small staff. They were literally doing this by hand sitting around as a team on lab benches trying to make 1000s of "test kits".
Next thing you know you have all hands on deck in a the CDC labs acting as a clinical supplies manufacture, something they never do.