Artificial intelligence expert Robert Wilensky dies at 61

Sick people go to the hospital in the first place so they often die there irregardless of the source of there injury's. Infections are often related to a compromised immune system / wounds so your risks are a lot higher in a hospital than say an office setting.

Also, Bactria exchange genetic material on a regular basis so things often concentrate in hospitals even if the source of the mutation is on a farm somewhere. The good news is that super bugs often provoke a strong response from the healthcare community which can quarantine the people / area and generally stop the spread of specific agents.

PS: What makes this even more frightening is you can't safely do operations without antibiotics as they basically guarantee infection.