A Sequalae of Lineage Divergence in from Community-Acquired Patterns in Youth to Hospital-Associated Profiles in Seniors Implied Age-Specific Host-Selection from a Common Ancestor.

The rapidly changing epidemiology of and evolution of strains with enhanced virulence is a significant issue in global healthcare. Hospital-associated methicillin-resistant (HA-MRSA) lineages are being completely replaced by community-associated (CA-MRSA) in many regions. Surveillance programs tracing the reservoirs and sources of infections are needed.