Ours is still open and running normally, despite us being under "shelter in place" and "no more than two people in a group" orders. The barn owner isn't the best at handling things like this. As far as I have heard, the only guidance she has issued is "don't share stuff."
As a precaution, I am washing hands before and after, and someone else had the suggestion of wiping down gates. Our horses live in the pasture, although they have reserved stalls. There are multiple barns on the property, and no one else uses the barn we use. We don't share horses or tack with anyone anyway. Our only point of contact with others is the gate.
Someone else on HF who boarded mention a two boarder at a time limit as well. But to me, since we have a very large (30+ acres) place, and we sort of have our own barn, this wouldn't really make sense. I hope we don't get to that. Going to see our horses is like our mental relaxation place.
I guess, though, that two boarders at a time is better than being closed altogether.
"Saddle fit -- it's a no brainer!"" - random person