@MARSKA, as with so many things in life I think this is very individual.
I'm a little surprised that you as a nurse suffer in this way because I would have thought that your immune system would have been more robust or adaptable than the general populace, however it is what it is. Perhaps in your case it is the 'straw that broke the camels back' syndrome.
it is not pleasant to be alone and ill anywhere - esp in a country not your own
I could not agree more. It has only happened to me once in 40 years but when it did it was pretty rough.
I'm fortunate, I'm more like
@Roland49 in this regard.
Whilst I appreciate your desire to stay in the munis perhaps you could break it up a little more right at the beginning (eg a private room every few nights) in order to give your body a little more chance?
You talk about modifying your behaviour, I assume that also includes the things that I do. By that I mean eat far more high vitamin C fruit (Kiwi etc) than usual, drink 2 or more wonderful fresh OJ daily, snack on dried fruit and so on. (Basically concentrate for the first week on eating more healthily than usual.) After that hiker hunger kicks in and I kind of figure that my body has adapted anyway!
As a nurse, perhaps it would be worthwhile asking a colleague who specialises in respiratory issues for preventive advice? I appreciate that you will probably know the majority of it anyway but who knows you might just be gifted a gem of information.