The problem is, they are correct.
You want to let a rabid dog loose in a kindergarten?
By the same token, a confirmed ebola outbreak in NY changes the rules.
Solution - stay the heck out of NYC.
Self quarantine by staying away from cities period.
Several years ago there was that movie about a dirty bomb (or two?) going off in London. Raised lots of the same things - except for the legal force behind it.
Obviously it won’t be business as usual if a dirty bomb goes off and contaminates 50,000+ people (and their clothes, documents, vehicles, merchandise, etc.) in the middle of NYC.
I didn’t even go on the senior trip to NYC back when it really was the “Big Apple”, I am certainly not going there now that it is the big trash dump. My closest approach was passing through Brooklyn Naval Shipyard on the way to Keflavik, Iceland and back.