To protect the patients who have open wounds.
My husband has been in and out of the hosp more times then i'd like to count the past 2 yrs. This last time he went in, with a barely open wound, it was infected with MRSA. They swabbed it when he went in for that surgery and there was no MRSA there. We'd been having nurses come into our house to do the dressings and deal with the picc line. I have NO doubt that one of those nurses picked it up somewhere and gave it to him. btw, It cost him his leg up to his calf.