E coli

VTEC (verotoxigenic E. coli, also known as shiga-toxigenic E. coli - STEC) such as E. coli  O157:H7 have been recognised since the 1980s as causes of severe, potentially fatal enterocolitis.  Additionally, infection with this type of bacteria can lead to complications such as haemolytic uraemic syndrome (HUS) which can result in kidney failure and even death of affected persons.  Infection by VTEC is rare (HPS Surveillance Report “Gastro-intestinal and foodborne infections”) although it continues to occur sporadically and in occasional outbreaks in Scotland as well as in other countries.

Although E. coli O157:H7 is the commonest VTEC associated with human disease in the UK, other types (e.g. O26, O121 & O145; each of which are common on the European mainland) cause a small number of cases (see, for example, Scottish E. coli O157/VTEC Reference Laboratory Annual Report for 2008-2009).

Despite causing potentially severe disease in humans, particularly the young and elderly, VTEC are normal, harmless residents of the intestinal tract of animals, principally cattle and sheep.  In addition to foodborne transmission, VTEC can be acquired more directly from contaminated environmental sources. 

Our work on VTEC covers:

• application of mass spectrometry for rapid identification and typing of VTEC, particularly E. coli O157:H7;
• characterisation of intestinal epithelial responses to infection with E. coli O157:H7;
• appraisal of novel approaches for immunisation of cattle to reduce their colonization by E. coli O157:H7.

The latter topic was part-funded by an industrial partner and represents a collaboration between investigators at the University of Edinburgh Roslin Institute, the Scottish Agricultural College (SAC) and Moredun Research Institute.