What is the name of the staph infection is it mercia?

See below: Mrsa (mercia?) methicillin resistant staph aureus.

MRSA: Staph is a common germ, lives on skin, in nose, elsewhere-ubiquitous. When get where they don't belong, cause infection including pus pockets (abscesses). Some strains are resistant to multiple antibiotics. One such strain is MRSA (methicillin resistant staph. Aureus); can be a big deal id there's infection with limited antibiotc available to rx. Don't want it to spread in hospitals, a big deal.