What is mrsa, why does it pose serious health risk especially for health care professional, and how is antibiotic resistance an example of evolution?

Oh I love this question. "MRSA" or "Mithicillin resistant staphylococcus aeues" is bacterial infection.

MRSA is unique to bacteria for it's ability to replicate and maintain homeostasis even when an antibiotic in introduces to destroy it. This resistance can have dangerous consequences usually mainly due to the requirement of needing aggressive in hospital treatment, its tendency to spread fast, and its ability to hit you so hard you could go into Sepsis. Its additionally dangerous because it's prevalent in the hospital.

While many people like to blame doctores for, "over prescribing" of antibiotics the fault doesn't't rest with a provider. In regards to evolution when a person is sick with a a common staphy infection people are prescribed antibiotic. The patient is required and usually specifically told to take the full course. The reason why is because the bacteria that would cause MRSA would still not have developed but are still alive following a treatment... However they gain the ability to become antibiotic resistant if the full course of antibiotics are not followed to a "T".