I don’t think it’s the fact that more people than others get colds etc, it’s their susceptibility to just putting up with it.
I work outside permanently and am out with dogs most of the time when I’m not working. I get the odd stuffy nose etc but it’s only a common cold, just get on with it, I know some lads that are constantly complaining of man flu etc and in bed with the lemsips, f*cking wimps need to man up ffs.