Development and validation of methods for the detection and identification of sorbitol-fermenting E.coli O157:H-

Last updated:
22 October 2007
This project aims to develop new methods that can be used for the detection and identification of atypical sorbitol-fermenting strains of Escherichia coli O157:H-.
Study duration: October 2007 to March 2011
Project code: B11013
Contractor: Scottish Agricultural College, Animal Health Research Group
Contact:

For any enquiries relating to this project please contact CST@foodstandards.gsi.gov.uk

Background

Verocytotoxin producing Escherichia coli (VTEC), is an important human pathogen and, in the UK, strains belonging to serotype O157:H7 have been predominantly associated with outbreaks of haemorrhagic colitis and haemolytic uraemic syndrome, two potentially life-threatening conditions.

E. coli O157:H7 related disease in humans in the UK has typically been caused by non sorbitol-fermenting VTEC O157:H7. However, atypical sorbitol-fermenting strains have recently emerged in the UK which cannot be identified on the standard detection media. This project therefore aims to develop new methods that can be used for the detection and identification of sorbitol-fermenting strains of Escherichia coli O157:H-.

A validated detection method will enable the food industry to inform food safety management systems, to support enforcement authorities and to facilitate the identification and tracing of surbitol-fermenting VTEC O157:H- organisms causing illness. This will support the Agency’s strategy to further reduce foodborne disease.

Research Approach

SF E. coli O157:H- bacteria have been shown by the research group to bind and accumulate a dye leading to formation of bright red colonies. These findings will be extended to optimise an identification medium and develop a laboratory detection procedure. A multiplex polymerase chain reaction to detect virulence genes in target isolates will also be developed. The study will validate, with statistical analysis, the detection procedures and compare them with current laboratory protocols.

Results

Additional Info

Dissemination

Published Papers