CEN ISO/TS 13136:2012

Foreword
Introduction
1 Scope
2 Normative references
3 Terms and definitions
4 Principle
5 Diluents, culture media and reagents
6 Equipment
7 Sampling
8 Preparation of test sample
9 Procedure
10 Expression of results
11 Performance data
Annex A (normative) - Flow diagram of the
        screening procedure
Annex B (normative) - Flow diagram of the
        isolation and confirmation procedure
Annex C (informative) - Identification of Shiga
        toxin-producing Escherichia coli
        (STEC) by multiplex PCR amplification
        of virulence genes and detection of PCR
        products by agarose gel electrophoresis
Annex D (informative) - Internal amplification control
Annex E (informative) - Primers and probes for the
        PCR assays
Annex F (normative) - Isolation of STEC strains
Bibliography

ISO/TR 13136:2012 describes the identification of Shiga toxin-producing Escherichia coli (STEC) by means of the detection of the following genes: a) the major virulence genes of STEC, stx and eae; b) the genes associated with the serogroups O157, O111, O26, O103, and O145.In any case, when one or both of the stx genes is/are detected, the isolation of the strain is attempted.The isolation of STEC from samples positive for the presence of the genes specifying the serogroups in the scope of this method can be facilitated by using serogroup-specific enrichment techniques (e.g. immunomagnetic separation, IMS).The protocol uses real-time PCR as the reference technology for detection of the virulence and serogroup-associated genes.ISO/TR 13136:2012 is applicable to: 1) products intended for human consumption and the feeding of animals; 2) environmental samples in the area of food production and food handling; 3) environmental samples in the area of primary production.