Enteroaggregative, Shiga toxin-producing Escherichia coli O104:H4 outbreak: new microbiological findings boost coordinated investigations by European public health laboratories.

In the past weeks, we witnessed the unfolding story of one of the largest ever reported outbreaks of haemolytic uremic syndrome (HUS) and bloody diarrhoea caused by Shiga toxin-producing Escherichia coli (STEC), also commonly referred to as verocytotoxinproducing E. coli (VTEC) and enterohaemorrhagic E. coli (EHEC) [1]. This outbreak has caused considerable suffering and resulted in a strain on healthcare and public health systems in parts in Germany. It has shown a number of striking features: an unusually large proportion of HUS cases as compared with diarrhoea cases [1]. Furthermore, whereas usually HUS triggered by STEC infection predominantly affects young children, the great majority of cases in this outbreak are adults and two thirds are women. Between 2 May and 14 June 2011, 3,332 STEC cases, including 818 cases of HUS, were reported from 13 European Union(EU)/ European Economic Area (EEA) Member States and 36 patients have died [2]. Over 95% of STEC cases have been reported from Germany and the vast majority of cases reside in or have a history of recent travel to northern Germany. Additional cases related to the outbreak have been reported from Switzerland, the United States and Canada [3]. However, since 10 June, there has been a clear signal that the number of newly reported HUS and STEC cases is gradually decreasing, which suggests that we may finally be reaching the tail end of the outbreak.