It's literally everywhere. I don't understand how we can avoid it.
We set out petri dishes in the classroom in microbiology and all kinds of bacteria and fungi landed in it.
I remember raking leaves and jumping into them as a kid. That could've been how I got it. I've had a stuffed up nose as long as I can remember.
But, the nasal irrigation really helps, and with the kefir in it I'm hoping this will be the cure, and for you you too! I just used it and it was less irritating than with plain water, or salt water. When it goes through your nose you feel it in your eye. I think they're all connected; ear, nose and eyes.