If WDW opens before there is a vaccine or cure for the virus, then WDW would be the last place other than an airport that I would ever want to work. People that have spent thousands on a vacation to WDW are some of the last ones on the planet that will not put it off if they just feel a tiny bit under the weather, and when a large percentage of those currently infected with the virus either feel no symptoms or extremely mild symptoms... well wellcome a perfect petri dish for the virus. If anyone had a clue that worked at WDW they would demand hazard pay for working there now.
If no vaccine or cure is found soon then I expect as things get back to normal and this becomes a seasonal virus, then places like WDW and schools would be best served to start requiring testing for the virus prior to admittance... for place like WDW you would expect it to happen the first day they arrive... for schools you would want it to happen on a fairly regular basis for both the student and any household members of the student. It might be expensive but something like that is what you would end up doing with a virus like this.