I would not be surprised if the next person to become infected will be someone who was picking up waste and cleaning the room. In other words, the lowest paid of the bunch. I also would not be surprised if we find out there are a lot more already infected.
Trained people who are really skilled at cleaning the room know how to avoid infection and keep things clean and sanitary. It's the marginal staff...the part-timers who can't afford to take a day off from work, maybe aren't all that bright or dedicated, who don't have a bond to the professional staff that are a problem.
This was my observation from being quarantined with the symptoms of swine flu (not swine flu) five years ago. It was when those top-tier professionals weren't on duty, not many protocols were strictly followed. And nobody can work 24/7. I wonder if there are enough well-trained and truly qualified top-tier employees to manage a hospital under constant threat of Ebola and all the other diseases that could get out of control.