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Extra-intestinal pathogenic Escherichia coli (ExPEC) are the predominant cause of Gramnegative bloodstream infections. In this study, 20 E. coli isolates that were the causative agents of bacteraemia and subsequent mortality were characterized. Whole-genome sequencing was used to define the predominant sequence types (ST) among the isolates and to identify virulence factors associated with pathogenicity of ExPEC. The ability of the isolates to resist killing by both serum and polymorphonuclear leukocytes (PMNLs) was also assessed. In line with global trends, ST131 occurred most frequently among the bloodstream isolates and all isolates of this sequence type were multidrug resistant. Other common STs included ST73 and ST69. All isolates encoded multiple virulence factors across a range of categories, including factors involved in adhesion, immune evasion, iron acquisition and synthesis of toxins. None of these factors could be associated with serum and neutrophil resistance. The majority of isolates were resistant to the bactericidal action of serum and PMNLs, and most of those that were sensitive were isolated from patients with compromised immunity. INTRODUCTIONRates of Escherichia coli bacteraemia have increased steadily in recent years (de Kraker et al., 2013). Concurrently, rates of multidrug resistant (MDR) E. coli infections are on the rise. In particular, the predominant extra-intestinal pathogenic E. coli (ExPEC) global lineage sequence type (ST) 131 is frequently associated with fluoroquinolone resistance and production of extended-spectrum b-lactamases (ESBLs) (Nicolas-Chanoine et al., 2014).Unlike other commensals found in the gastrointestinal tract (GT), ExPEC have an associated array of virulence factors that allow survival outside of this setting. Many of these virulence factors have been horizontally acquired and vary from strain to strain (Dobrindt et al., 2003). They can be classed into adhesins, protectins, iron acquisition systems and toxins (Köhler & Dobrindt, 2011). Adhesins, such as the type 1 fimbriae, contribute to colonization of the urinary tract (UT) epithelium (Kaper et al., 2004;Mulvey et al., 2000; Ulett et al., 2013). The UT is the most common source of infection in cases of bacteraemia (Russo & Johnson, 2003). Access to the bloodstream follows an ascending infection in which the F1C and P fimbriae play a role (Kaper et al., 2004;Mulvey et al., 2000). Many other adhesins have been associated with pathogenesis of E. coli, including S fimbriae, the Hek adhesin, antigen 43, the temperature-sensitive haemagglutinin (Tsh), F9 fimbriae and the Iha adhesin (Fagan & Smith, 2007; Köhler & Dobrindt, 2011;Ulett et al., 2007;Wurpel et al., 2014).ExPEC that cross the tubular epithelial cell barrier and enter the bloodstream can induce a powerful host inflammatory response, resulting in sepsis. Sepsis is associated with high rates of morbidity and mortality (Laupland et al., 2008;Russo & Johnson, 2003). To survive in the bloodstream, E. coli have to resist immune defences of the host, includin...

Context Old, evolving, and new infectious agents continually threaten the participation of competitors in sports. Objective To provide an update of the medical literature on infectious disease outbreaks in sport for the last 5 years (May 2005–November 2010). Main Outcome Measure(s) A total of 21 outbreaks or clusters were identified. Results Methicillin-resistant Staphylococcus aureus (n = 7, 33%; mainly community acquired) and tinea (trichophytosis: n = 6, 29%) were the most common pathogens responsible for outbreaks. Skin and soft tissue was the most common site of infection (n = 15, 71%). Conclusions The majority of outbreaks reported occurred in close-contact sports, mainly combat sports (ie, wrestling, judo) and American football. Twelve outbreaks (57%) involved high school or collegiate competitors. Common community outbreak pathogens, such as influenza virus and norovirus, have received little attention.

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