1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS EN ISO 22118:2011Microbiology of food andanimal feeding stuffs Polymerase chain reaction(PCR) for the detection andquantification of food-bornepathogens Performancecharacteris
2、tics (ISO 22118:2011)BS EN ISO 22118:2011 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of EN ISO 22118:2011.The UK participation in its preparation was entrusted to Technical Committee AW/9, Microbiology.A list of organizations represented on this committee can be
3、obtained on request to its secretary.This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. BSI 2011 ISBN 978 0 580 60372 3 ICS Compliance with a British Standard cannot confer immunity from legal obligations.This B
4、ritish Standard was published under the authority of the Standards Policy and Strategy Committee on 31 August 2011.Amendments issued since publicationDate T e x t a f f e c t e dEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 22118 July 2011 ICS 07.100.30 English Version Microbiology of foo
5、d and animal feeding stuffs - Polymerase chain reaction (PCR) for the detection and quantification of food-borne pathogens - Performance characteristics (ISO 22118:2011) Microbiologie des aliments - Raction de polymrisation en chane (PCR) pour la dtection et la quantification des micro-organismes pa
6、thognes dans les aliments - Caractristiques de performance (ISO 22118:2011) Mikrobiologie von Lebensmitteln und Futtermitteln - Polymerase-Kettenreaktion (PCR) zum Nachweis und zur quantitativen Bestimmung von pathogenen Mikroorganismen in Lebensmitteln - Leistungsmerkmale (ISO 22118:2011) This Euro
7、pean Standard was approved by CEN on 14 July 2011. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references conc
8、erning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member in
9、to its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Irel
10、and, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 1
11、7, B-1000 Brussels 2011 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 22118:2011: EBS EN ISO 22118:2011EN ISO 22118:2011 (E) 3 Foreword This document (EN ISO 22118:2011) has been prepared by Technical Committee CEN/TC 275 “Fo
12、od analysis - Horizontal methods”, the secretariat of which is held by DIN, in collaboration with Technical Committee ISO/TC 34 “Food products”. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by Jan
13、uary 2012, and conflicting national standards shall be withdrawn at the latest by January 2012. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such paten
14、t rights. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Icelan
15、d, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. BS EN ISO 22118:2011ISO 22118:2011(E) ISO 2011 All rights reserved iiiForeword ISO (the International Organization for Stand
16、ardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right
17、to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. International St
18、andards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2. The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an I
19、nternational Standard requires approval by at least 75 % of the member bodies casting a vote. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. ISO 221
20、18 was prepared by the European Committee for Standardization (CEN) Technical Committee CEN/TC 275, Food analysis Horizontal methods, in collaboration with Technical Committee ISO/TC 34, Food products, Subcommittee SC 9, Microbiology, in accordance with the Agreement on technical cooperation between
21、 ISO and CEN (Vienna Agreement). BS EN ISO 22118:2011ISO 22118:2011(E) iv ISO 2011 All rights reservedIntroduction Molecular detection methods have been developed during the last few decades, and are now available for the majority of food-borne pathogens. Some of these methods have the potential for
22、 quantitative analysis. Although until now most methods have been based on the polymerase chain reaction (PCR) and real-time PCR, other molecular detection and quantification principles should be kept under consideration. To compare molecular methods with conventional methods or with other principle
23、s, it is necessary to generate minimum requirements for performance characteristics of the methods to be developed. This International Standard is part of a series of documents under the general title Microbiology of food and animal feeding stuffs Polymerase chain reaction (PCR) for the detection of
24、 food-borne pathogens: ISO/TS 20836, Microbiology of food and animal feeding stuffs Polymerase chain reaction (PCR) for the detection of food-borne pathogens Performance testing for thermal cyclers ISO 20837, Microbiology of food and animal feeding stuffs Polymerase chain reaction (PCR) for the dete
25、ction of food-borne pathogens Requirements for sample preparation for qualitative detection ISO 20838, Microbiology of food and animal feeding stuffs Polymerase chain reaction (PCR) for the detection of food-borne pathogens Requirements for amplification and detection for qualitative methods ISO 221
26、18, Microbiology of food and animal feeding stuffs Polymerase chain reaction (PCR) for the detection and quantification of food-borne pathogens Performance characteristics ISO 22119, Microbiology of food and animal feeding stuffs Real-time polymerase chain reaction (PCR) for the detection of food-bo
27、rne pathogens General requirements and definitions ISO 22174, Microbiology of food and animal feeding stuffs Polymerase chain reaction (PCR) for the detection of food-borne pathogens General requirements and definitions The following Technical Specification is in preparation: ISO/TS 13136, Microbiol
28、ogy of food and animal feeding stuffs Horizontal method for the detection of Shiga toxin-producing Escherichia coli (STEC) belonging to O157, O111, O26, O103 and O145 serogroups Qualitative real-time polymerase chain reaction (PCR)-based method BS EN ISO 22118:2011INTERNATIONAL STANDARD ISO 22118:20
29、11(E) ISO 2011 All rights reserved 1Microbiology of food and animal feeding stuffs Polymerase chain reaction (PCR) for the detection and quantification of food-borne pathogens Performance characteristics 1 Scope This International Standard specifies minimum requirements of performance characteristic
30、s for the detection of nucleic acid sequences (DNA or RNA) by molecular methods. This International Standard applies to the detection of food-borne pathogens in foodstuffs and isolates obtained from them using molecular detection methods based on the polymerase chain reaction (PCR). This Internation
31、al Standard is also applicable, for example, to the detection of food-borne pathogens in environmental samples and in animal feeding stuffs. NOTE Because of the rapid progress in this field, the examples given are those most frequently in use at the time of development of this International Standard
32、. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 16140:2003, Microbio
33、logy of food and animal feeding stuffs Protocol for the validation of alternative methods ISO 22174:2005, Microbiology of food and animal feeding stuffs Polymerase chain reaction (PCR) for the detection of food-borne pathogens General requirements and definitions 3 Terms and definitions For the purp
34、oses of this document, the following terms and definitions apply. 3.1 analyte component detected or measured by the method of analysis NOTE 1 The analyte can be a microorganism or virus, its components or products. NOTE 2 Adapted from ISO 16140:2003, 3.4. 3.2 qualitative method method of analysis wh
35、ose response is either the presence or absence of the analyte detected either directly or indirectly in a certain amount of sample ISO 16140:2003, 3.5. BS EN ISO 22118:2011ISO 22118:2011(E) 2 ISO 2011 All rights reserved3.3 quantitative method method of analysis whose response is the amount of the a
36、nalyte measured either directly or indirectly in a certain amount of sample NOTE Adapted from ISO 16140:2003, 3.6. 3.4 robustness testing food microbiology subjecting the proposed method to small procedural changes or environmental factors to determine what influence, if any, they have on method per
37、formance 3.5 selectivity food microbiology measure of the inclusivity (detection of the target microorganism or virus) and exclusivity (non-detection of non-target microorganisms or viruses) 3.6 sensitivity food microbiology measure of the lowest number of analyte cells, particles or molecules which
38、 can be detected in a single reaction 3.7 specificity capacity to exclusively recognize the target to be detected, distinguishing it from similar substances and impurities ISO 22174:2005, 3.6.4 3.8 trueness closeness of agreement between the expectation of a test result or a measurement result and a
39、 true value ISO 3534-2:20061, 3.3.3 3.9 detection limit limit of detection LOD lowest concentration or content of the target organism relative to the defined amount of matrix that can be consistently detected under the experimental conditions specified in the method NOTE Adapted from ISO 22174:2005,
40、 3.1.8. 3.10 quantification limit limit of quantification LOQ food microbiology smallest amount of analyte (that is the lowest actual number of organisms), which can be measured and quantified with defined trueness and precision under the experimental conditions by the method under validation NOTE A
41、dapted from ISO 16140:2003, 6.2.2.2.3. 3.11 precision closeness of agreement between independent test/measurement results obtained under stipulated conditions BS EN ISO 22118:2011ISO 22118:2011(E) ISO 2011 All rights reserved 3NOTE 1 Precision depends only on the distribution of random errors and do
42、es not relate to the true value or the specified value. NOTE 2 The measure of precision is usually expressed in terms of imprecision and computed as a standard deviation of the test results or measurement results. Less precision is reflected by a larger standard deviation. NOTE 3 Quantitative measur
43、es of precision depend critically on the stipulated conditions. Repeatability conditions and reproducibility conditions are particular sets of extreme stipulated conditions. ISO 3534-2:2006 1, 3.3.4 4 Performance characteristics of qualitative and quantitative detection methods 4.1 General A molecul
44、ar detection method shall meet performance characteristics according to this International Standard. Information about the performance characteristics of the molecular detection method shall be made available. This includes specific information on the multi- or single-laboratory trial, including rel
45、evant information obtained during pre-validation of the method (e.g. variation of parameters, reagents). 4.2 Scope of the method The purpose of the method should be indicated. Information regarding the intended use and the limitations of the methods shall be provided. In particular, the method provi
46、der shall indicate that the criteria set out in this International Standard are fulfilled. 4.3 Scientific basis An overview of the principles and references to relevant scientific publications should be provided. 4.4 Selectivity 4.4.1 Inclusivity test 4.4.1.1 General Empirical results from testing t
47、he method with the target microorganism or viruses should be provided. This testing should include all relevant variants or types of the microorganism or viruses according to the scope of the method (4.2). 4.4.1.2 Minimum requirements for specificity Sequence variants of the target microorganism or
48、viruses should be detected with comparable amplification efficiency, even if sequence differences in the primer and/or probe binding sites are present as indicated by the scope of the method (4.2). If available, 50 strains of the specific target microorganism or virus should be tested. 4.4.2 Exclusi
49、vity test 4.4.2.1 General Empirical results from testing the method with non-target microorganisms or viruses should be provided. This testing should include both taxonomically closely related and not closely related microorganisms or viruses. The method should clearly distinguish between target and non-target microorganisms or viruses. BS EN ISO 22118:2011ISO 22118:2011(E) 4 ISO 2011 All rights reserved4.4.2.2 Test systems for detecting bacteria Select a minimum of 30 strains that may cau
