The proficiency testing program of the European Union Reference Laboratory for E. coli

Abstract

Since 2006, the European Union Reference Laboratory for E. coli (EU-RL) has developed and evaluated standard operating procedures for the identification and typing of verocytotoxin-producing Escherichia coli (VTEC) and for their detection in food, mainly based on PCR detection of virulence genes. In particular, the EU-RL coordinated the development of the Technical Specification ISO TS 13136:2012 on the detection of VTEC in food and animal feed, based on the real-time PCR screening of food enrichment cultures. A total of 13 proficiency testing (PT) rounds were organized: 7 PTs on the identification and typing of VTEC and other pathogenic E. coli strains (detection of virulence genes by PCR and identification of the VTEC serogroups by serological and molecular methods) and 6 PTs on the detection of VTEC in different matrices (carcass swabs, milk, spinach, water, seeds and sprouts), analyzed by using the ISO TS 13136 method. A Web-based platform for submitting the PT results was developed and used since 2010. Between 2007 and 2014, a positive trend was observed in both the number of participants and their performance. Through its PT program, the EU-RL has consolidated a network of reference laboratories for the control of pathogenic E. coli in the EU Member States. Such a network can contribute to gather harmonized data on the prevalence of VTEC in food, to improve the knowledge of the epidemiology of VTEC infections in Europe, and to provide the EC with more standardized operative structures and tools to face possible emergencies in this field of food safety.