I am not going to theorize about the how or the why, for all I know the lab could have mixed up samples.
Definitely a possibility, as I said upthread. Would also explain why it wasn't happening in Israel- there were simply no cases to mix up.
I do know for sure that I was told that my test came back positive, and I am equally certain that I did not have covid-19 at the time that test was taken.
I'm not doubting you are, but how can you be certain?
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