Autistic moment here
What if the COVID-19 tests, being done now, show residuals of a previous vaccination?
For example, if you were previously vaccinated for the flu (and this virus was contained in this vaccine, as a precautionary measure - they try to predict several years ahead - a guessing game at best), you would test positive, although you were never really exposed to the one that is out their today.
Your immune system would show the antibodies, and thus, you are positive