Characterisation of the Escherichia coli strain associated with an outbreak of haemolytic uraemic syndrome in Germany, 2011: a microbiological study

Escherichia coli virulence factors

“…In vivo pathogenic EAggEC not only adhere to enterocytes and to the extracellular intestinal matrix, but also form mucoid biofilms at the surface of the intestinal epithelium of the terminal ileum and of the colon (Nataro, 2005;Weintraub, 2007;Farfan et al, 2008). The recent outbreak of haemorrhagic colitis and haemolytic-uremic syndrome in Germany was caused by one EAggEC having acquired the genes coding for a verotoxin (see Section 4) by horizontal transfer by phage transduction Bielaszewska et al, 2011;Scheutz et al, 2011). Such AAFpositive E. coli strains have not been described in animals yet.…”

Shiga toxin-producing Escherichia coli O104:H4: An emerging important pathogen in food safety

“…This strain could produce Shigatoxin 2 and belonged to sequence type 678, which was same as the 2011 outbreak strains [33]. Unfortunately, no detailed report exists on the symptoms of the patients from whom this strain was isolated.…”

“…The outbreak strain turned out to be an unusual combination of the pathogenic features of "stacked brick" aggregation of adherence to HEp2-cells in culture, which is typical of EAEC, and of Shiga toxin production, which is typical of EHEC [36]. Compared with HUSEC041 that was isolated in 2001, the outbreak strain acquired an extended-spectrum -lactamase phenotype as well as resistance to many other types of antibiotics [33]. Detection of other virulence-associated genes characterizing both EAEC and EHEC indicated that the virulence backbone of the outbreak strain should be EAEC.…”

“…Nevertheless, the extensive characterization of this pathogen only began in 2011 due to the widespread outbreak [33,36]. The outbreak strain turned out to be an unusual combination of the pathogenic features of "stacked brick" aggregation of adherence to HEp2-cells in culture, which is typical of EAEC, and of Shiga toxin production, which is typical of EHEC [36].…”

“…Detection of other virulence-associated genes characterizing both EAEC and EHEC indicated that the virulence backbone of the outbreak strain should be EAEC. In addition, bacteriophage-encoding Shiga toxin 2 was acquired from EHEC or an unknown environment, along with other antibiotics-resistant genes from unknown sources [33,[36][37][38]. …”