Something I thought of last night: They don't need a test to see if you have the CV. They need a test to see if you have HAD the CV.
it seems to me that both kinds of tests already exist, even though there are a variety of techniques to accomplish and of course, shortages of tests and even logistical issues regarding who and how to test.
The "already had" CV test is testing for the presence of CV anti-bodies, I believe.That's correct.
have CV-either immunological for surface protein (less sensitive, probably) or PCR-for viral genomes.
had CV-test for presence of antibodies. This test would become progressively more important as we move forward as we need to ID people who already had it and are possibly immune. These people could do things that others can't.
The only caveat is that the amount of antibodies in the bloodstream would be declining steadily after infection is over, maybe over a couple of months or a bit more.
After that you are still protected, usually, by the presence of so called memory cells (both T- and B-) which spring into action IMMEDIATELY after re-infection and not allow new viral growth.
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