Geographic distribution of Staphylococcus aureus causing invasive infections in Europe: a molecular-epidemiological analysis

• Published in: PLoS medicine Vol. 7; no. 1; p. e1000215
• Main Authors: Grundmann, Hajo, Aanensen, David M, van den Wijngaard, Cees C, Spratt, Brian G, Harmsen, Dag, Friedrich, Alexander W
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 01-01-2010; Public Library of Science (PLoS)
• Subjects: Adolescent; Adult; Age Distribution; Aged; Aged, 80 and over; Bacterial Typing Techniques; Bacteriology; Biological diversity; Child; Child, Preschool; Cluster Analysis; Communicable Disease Control; Cross infection; Distribution; DNA, Bacterial - isolation & purification; Epidemiologic methods; Europe - epidemiology; Forecasts and trends; Genotype; Health Surveys; Humans; Infant; Infection Control; International aspects; Laboratories; Methicillin-Resistant Staphylococcus aureus - classification; Methicillin-Resistant Staphylococcus aureus - genetics; Methicillin-Resistant Staphylococcus aureus - pathogenicity; Microbiology; Middle Aged; Molecular Epidemiology; Nosocomial infections; Pathology, Molecular; Phenotype; Public Health and Epidemiology/Infectious Diseases; Public Health and Epidemiology/Nosocomial and Healthcare-Associated Infections; Residence Characteristics; Staphylococcal Infections - epidemiology; Staphylococcal Infections - microbiology; Staphylococcal Infections - prevention & control; Staphylococcal Infections - transmission; Staphylococcal Protein A - genetics; Staphylococcus aureus; Staphylococcus aureus infections; Staphylococcus infections; Young Adult; Europe; Residence Characteristics; Age Distribution; Humans; Middle Aged; Infection Control; Child, Preschool; Infant; DNA, Bacterial; Methicillin-Resistant Staphylococcus aureus; Young Adult; Bacterial Typing Techniques; Adult; Child; Europe; Genotype; Communicable Disease Control; Staphylococcal Protein A; Staphylococcal Infections; Aged, 80 & over; Phenotype; Health Surveys; Molecular Epidemiology; Adolescent; Aged; Cluster Analysis
• ISSN: 1549-1676; 1549-1277; 1549-1676
• DOI: 10.1371/journal.pmed.1000215

Staphylococcus aureus is one of the most important human pathogens and methicillin-resistant variants (MRSAs) are a major cause of hospital and community-acquired infection. We aimed to map the geographic distribution of the dominant clones that cause invasive infections in Europe.
In each country, staphylococcal reference laboratories secured the participation of a sufficient number of hospital laboratories to achieve national geo-demographic representation. Participating laboratories collected successive methicillin-susceptible (MSSA) and MRSA isolates from patients with invasive S. aureus infection using an agreed protocol. All isolates were sent to the respective national reference laboratories and characterised by quality-controlled sequence typing of the variable region of the staphylococcal spa gene (spa typing), and data were uploaded to a central database. Relevant genetic and phenotypic information was assembled for interactive interrogation by a purpose-built Web-based mapping application. Between September 2006 and February 2007, 357 laboratories serving 450 hospitals in 26 countries collected 2,890 MSSA and MRSA isolates from patients with invasive S. aureus infection. A wide geographical distribution of spa types was found with some prevalent in all European countries. MSSA were more diverse than MRSA. Genetic diversity of MRSA differed considerably between countries with dominant MRSA spa types forming distinctive geographical clusters. We provide evidence that a network approach consisting of decentralised typing and visualisation of aggregated data using an interactive mapping tool can provide important information on the dynamics of MRSA populations such as early signalling of emerging strains, cross border spread, and importation by travel.
In contrast to MSSA, MRSA spa types have a predominantly regional distribution in Europe. This finding is indicative of the selection and spread of a limited number of clones within health care networks, suggesting that control efforts aimed at interrupting the spread within and between health care institutions may not only be feasible but ultimately successful and should therefore be strongly encouraged.