DH was ill a few weeks ago. General man flu symptoms including a cough and a loss of smell and taste. He had a negative test and we all went back to work. Only it's now 3 weeks later and he still can't taste or smell anything (still hasn't quite got his voice back properly but that's a common symptom of viruses for him). How likely is it that its just a coincidence rather than a false negative? None of us got sick which points towards coincidence but I wish I could know for sure (just to satisfy curiosity rather than it actually mattering)