Forget all the horror stories, everybody carries the nasty bit that causes mrsa, but it only becomes a problem for some, very treatable, very under controll, so long as caught early enough, he'll be fine.
My dad has recently had all chemo for his voicebox cancer(voicebox removed), over months and months no problem.
It helps being fit and healthy(cancer apart) so should be all ok, I was in hosp 19 months and didn't get anything so they're pretty good.
tabetha