It's great that you want to be a considerate friend and that you're worried about the potential problems MRSA may cause. Keep in mind that EVERYONE's body contains staph, and unless your nursing friends are immunocompromised, their bodies are not likely to be infected with the resistant form of staph aureus.
Don't worry so much, and just remember to be diligent about handwashing when you've got a cough, and wearing a mask if you spend time with them in the hospital. Don't touch things that will come into contact with patients (i.e. towels, bedding, curtains, food trays, etc.) It's really unlikely that you'll cause a problem. Also, MRSA, although resistant to the methicillin family of antibiotics, it can be treated effectively with a combination of antibiotics, one of which is vancomycin.
I hope that helps allay your fears somewhat. You're a good friend to be concerned. I'm sure your nurse friends will be properly instructed in cross infection control methods. Don't put so much pressure on yourself.
All the best,
Lauren
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