It seems like it’s important to know both whether someone is currently infected so they can quarantine, and also whether they were previously infected and now immune and non contagious so they can carry on. Do or will tests factor both concerns?
At a minimum you’d need two different types of tests with two different sample types, i.e. a nasopharyngeal swab to test for active infection (via molecular testing methods) and a serological blood test to look for markers of immunity.
This is an old problem, but one that, until now, rarely needed to be addressed - at least on such a vast scale. Unfortunately there’s not much that could address both issues - and unlikely to be any time soon.
Is there evidence that surviving the infection provides immunity? Or are you just assuming such is the case?
Because I recall reading of people being able to contract it again. Don’t recall if it was proven definitively, in the end, but it was def being discussed seriously at one point, in Asia.
There are some people who’ve tested positive some time after seemingly recovered. Those cases are under investigation, and I don’t think we know if they’re really reinfected or something else (perhaps false positives).
But just because you have antibodies does not necessarily make you immune. Antibodies are made to combine with a protein or other chemical on the surface of an invader. But that part of the invader may not be critical to its function so the antibodies are ineffective. This does happen with some diseases, although I can’t remember which ones.
Lots of things I didn’t consider, thanks! But that does put into question then, what is the primary goal of the testing, if there are so many loopholes?
I mean it’s obvious why it’s generally better to have the test, but it seems like it’s being characterized as a key lynchpin in ending the pandemic, and that seems less obvious to me now.