If you follow this through to it's ultimate conclusion. You would expect every hotel mattress to be cleaned for every changeover, or at least to have every mattress protector changed.
Can't see it happen in your average hotel.
We had to de infest our mattress nightly in the Dominican Republic last year. Imagine living with that every night of your life ?
The accommodation was chalet type, rather than large building. We had a massive land crab in a hole about ten feet from the door and some holidaymakers saw strange rat like creatures scuttling around at night, a live snake even appeared in the swimming pool one day.
At least the stain in the mattress could be sterilised or at least covered !