title: Molecular epidemiology of community-associated methicillin-resistant Staphylococcus aureus in the genomic era: a cross-sectional study.
abstract: Methicillin-resistant Staphylococcus aureus (MRSA) is a leading cause of healthcare-associated infections and significant contributor to healthcare cost. Community-associated-MRSA (CA-MRSA) strains have now invaded healthcare settings. A convenience sample of 97 clinical MRSA isolates was obtained from seven hospitals during a one-week period in 2010. We employed a framework integrating Staphylococcus protein A typing and full-genome next-generation sequencing. Single nucleotide polymorphisms were analyzed using phylodynamics. Twenty-six t002, 48 t008, and 23 other strains were identified. Phylodynamic analysis of 30 t008 strains showed ongoing exponential growth of the effective population size the basic reproductive number (R0) ranging from 1.24 to 1.34. No evidence of hospital clusters was identified. The lack of phylogeographic clustering suggests that community introduction is a major contributor to emergence of CA-MRSA strains within hospitals. Phylodynamic analysis provides a powerful framework to investigate MRSA transmission between the community and hospitals, an understanding of which is essential for control.
authors.affiliation: College of Medicine, Department of Pathology, Immunology and Laboratory Medicine, University of Florida, Jacksonville, FL, USA.
authors.forename: Mattia
authors.initials: M
authors.lastname: Prosperi
authors.forename: Nazle
authors.initials: N
authors.lastname: Veras
authors.forename: Taj
authors.initials: T
authors.lastname: Azarian
authors.forename: Mobeen
authors.initials: M
authors.lastname: Rathore
authors.forename: David
authors.initials: D
authors.lastname: Nolan
authors.forename: Kenneth
authors.initials: K
authors.lastname: Rand
authors.forename: Robert L
authors.initials: RL
authors.lastname: Cook
authors.forename: Judy
authors.initials: J
authors.lastname: Johnson
authors.forename: J Glenn
authors.initials: JG
authors.lastname: Morris
authors.forename: Marco
authors.initials: M
authors.lastname: Salemi
mesh_terms: D015373:Bacterial Typing Techniques; D017714:Community-Acquired Infections / Q000453:epidemiology* / Q000235:genetics / Q000382:microbiology; D003430:Cross-Sectional Studies; D016172:DNA Fingerprinting; D004269:DNA, Bacterial / Q000032:analysis / Q000235:genetics; D023281:Genomics; D005838:Genotype; D059014:High-Throughput Nucleotide Sequencing; D006761:Hospitals; D006801:Humans; D055624:Methicillin-Resistant Staphylococcus aureus / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D008826:Microbial Sensitivity Tests; D017720:Molecular Epidemiology; D010802:Phylogeny; D013203:Staphylococcal Infections / Q000453:epidemiology* / Q000235:genetics / Q000382:microbiology
chemical_list: D004269:DNA, Bacterial