Importance Estimating the US burden of methicillin-resistantStaphylococcus aureus (MRSA)
infections is important for planning and tracking success of prevention strategies. Objective
To describe updated national estimates and characteristics of health care–and community-
associated invasive methicillin-resistantStaphylococcus aureus (MRSA) infections in 2011.
Design, Setting, and Participants Active laboratory-based case finding identified MRSA
cultures in 9 US metropolitan areas from 2005 through 2011. Invasive infections (MRSA …

Objective: To describe updated national estimates and characteristics of health care–and
community-associated invasive methicillin-resistant Staphylococcus aureus (MRSA)
infections in 2011. Design, Setting, and Participants: Active laboratory-based case finding
identified MRSA cultures in 9 US metropolitan areas from 2005 through 2011. Invasive
infections (MRSA cultured from normally sterile body sites) were classified as health care–
associated community-onset (HACO) infections (cultured≤ 3 days after admission and/or …