I haven't read all the previous messages in this thread (although quite a few) so I apologise if this has been mentioned before, but it is always worth considering whether the infestation is actually with animal fleas rather than bedbugs.

This is most likely if the hotel allows pets (mainly dogs) to stay in rooms with guests, and it is very common. The fleas lay eggs in the carpet and when these hatch they release ravenous fleas that will bite any passing animal, including humans!

There are some distinguishing features of this: the bites are mostly on feet/ankles and upper limbs rather than head and shoulders and body; they are said to be randomly distributed rather than in short lines of bites (although I have most certainly personally had cat flea bites in short lines on my ankles and lower legs - from our own cat!); they become itchy very soon after biting; you can often see fleas jumping on to your legs from the carpet; you get bitten at any time of day and not just at night. The bites are said to look different from bedbug bites but, despite being a medic, I am not confident I could reliably tell them apart just by looking at individual ones.

The most important thing is that cat & dog fleas will NOT travel with you or your belongings to your home or the next hotel: you might want to wash clothing etc but there is absolutely no need to throw anything away or freeze it or douse it in noxious chemicals. Cat & dog fleas only travel on cats or dogs.

Hope that helps.