As countries are losing control now, unexpected transmission is becoming an issue. I'm sure the cruise company would have been taking steps to exclude people from known infected areas but clearly that's not a guarantee any longer.
But the same basic issues apply to hotels and offices - anywhere where there's potential for close contact over a sustained period. We know that the virus can survive for 48 hours in the right environment and we know some people exhibit limited or no clear symptoms. I suspect that those are the basic ingredients for a virus to spread rapidly.
Supermarket trolleys and baskets? The conveyor belts on which you put the food. Indeed, any food that's going to be eaten raw (apples, grapes and so on). Almost everyone goes shopping.
Originally Posted by: Gandalf The White