I think most general hospitals are not designed for isolating infectious patients. Just visit any Canadian hospital and you can see there are very few single bed rooms
It's really not that suspicious; infectious viral diseases do spring up, and from the sounds of it the market in Wuhan was prime breeding ground for something to jump to humans.
Given it was also in the middle of winter and flu season, if there was any time in the year for it to happen it would've been about now.