Shift in dominant hospital-associated methicillin-resistant Staphylococcus aureus (HA-MRSA) clones over time.

Objectives: The majority of HA-MRSA infections are caused by endogenous infection and by only a small number of clones. The reasons for the success of some clones over others are unknown.

Methods: We investigated the evolution of an MRSA population from a large, acute-care teaching hospital in London, UK over a 10 year period.