Commission Implementing Decision (EU) 2020/1729Show full title

4. Antimicrobial susceptibility testing U.K.

4.1. Number of isolates to be tested U.K.

Member States shall test for antimicrobial susceptibility the following number of isolates annually and ensure that no more than one isolate per bacterial species/Salmonella serovar from the same epidemiological unit is tested per year:

For Salmonella spp:

• up to 170 isolates obtained from samples referred to in point 1(a)(i). Where Member States have a national annual production of less than 100 000 tonnes of broiler meat, they may decide to set an upper limit of 85 isolates instead of 170 isolates. The isolates shall be obtained from healthy animals. Where the number of isolates yearly available per animal population in a Member State is higher than the upper limit, a random selection of those isolates shall be performed in a way that ensures a geographical representativeness and, where possible, an even distribution of the date of sampling over the year. When the number of isolates yearly available is lower than the upper limit, all of them shall be tested,

• at least 170 isolates obtained from samples referred to in point 1(a)(ii) or, for Member States making use of the derogation referred to in the second paragraph of point 3(1)(b), all isolates obtained from these samples. By way of derogation, where Member States have a national annual production of less than 100 000 tonnes of pig meat, they may decide to test a minimum of 85 isolates instead of 170 isolates,

• at least 170 isolates obtained from samples referred to in point 1(a)(iii) or, for Member States making use of the derogation referred to in the second paragraph of point 3(1)(b), all isolates obtained from these samples,

• all isolates obtained from samples referred to in point 1(a)(iv).

For C. coli and C. jejuni:

• at least 170 isolates of the nationally most prevalent species of Campylobacter (among C. coli and C. jejuni) obtained from samples referred to in point 1(b)(i) to (iii) or, for Member States making use of the derogation referred to in the second paragraph of point 3(1)(b), all isolates obtained from these samples. By way of derogation, where Member States have a national annual production of less than 100 000 tonnes of broiler meat, they may decide to test a minimum of 85 isolates instead of 170 isolates,

• up to 170 isolates of the nationally less prevalent species of Campylobacter (among C. coli and C. jejuni) identified while recovering the isolates of the most prevalent Campylobacter species obtained from samples referred to in point 1(b)(i) to (iii),

• at least 170 isolates of C. coli obtained from samples referred to in point 1(b)(iv) or, for Member States making use of the derogation referred to in the second paragraph of point 3(1)(b), all isolates obtained from these samples. By way of derogation, where Member States have a national annual production of less than 100 000 tonnes of pig meat, they may decide to test a minimum of 85 isolates instead of 170 isolates.

For indicator commensal E. coli:

• at least 170 isolates obtained from samples referred to in points 1(c)(i) to (iv). By way of derogation, where Member States have a national annual production of less than 100 000 tonnes of broiler meat, less than 100 000 tonnes of turkey meat or less than 100 000 tonnes of pig meat, they may decide to test a minimum of 85 isolates instead of 170 isolates for each specific animal population considered,

• all isolates obtained from samples referred to in point 1(c)(v).

For ESBL-, AmpC- and CP- producing E. coli:

• all isolates obtained from samples referred to in point 1(d).

4.2. Analytical methods for detection and antimicrobial susceptibility testing U.K.

Member States shall use the epidemiological cut-off values and the concentration ranges set out in Tables 2, 3 and 4 below to determine the antimicrobial susceptibility of Salmonella spp., C. coli, C. jejuni, indicator commensal E. coli, E. faecalis and E. faecium.

Any E. coli and Salmonella isolate tested in accordance with Table 2 showing resistance to cefotaxime or ceftazidime or meropenem shall be further tested with a second panel of antimicrobial substances in accordance with Table 5.

For the specific monitoring of ESBL-, AmpC- and/or CP-producing E. coli, Member States shall use the methods referred to in point 5.

The antimicrobial susceptibility testing shall be performed by the laboratories referred to in Article 3(2). The testing shall be performed by using the broth micro dilution method according to the reference method ISO 20776-1:2019.

Table 2

Panel of antimicrobial substances to be included in AMR monitoring, EUCAST thresholds for resistance and concentration ranges to be tested in Salmonella spp. and indicator commensal E. coli (First panel)

a tentative EUCAST threshold
NA: not available.
Antimicrobial	Class of antimicrobial	Species	Interpretative thresholds of AMR (mg/L)		Range of concentrations (mg/L)(No of wells in brackets)
			ECOFF	Clinical breakpoint
Amikacin	Aminoglycoside	Salmonella	> 4a	> 16	4-128 (6)
		E. coli	> 8	> 16
Ampicillin	Penicillin	Salmonella	> 8	> 8	1-32 (6)
		E. coli	> 8	> 8
Azithromycin	Macrolide	Salmonella	NA	NA	2-64 (6)
		E. coli	NA	NA
Cefotaxime	Cephalosporin	Salmonella	> 0,5	> 2	0,25-4 (5)
		E, coli	> 0,25	> 2
Ceftazidime	Cephalosporin	Salmonella	> 2	> 4	0,25-8 (6)
		E, coli	> 0,5	> 4
Chloramphenicol	Phenicol	Salmonella	> 16	> 8	8-64 (4)
		E, coli	> 16	> 8
Ciprofloxacin	Fluoroquinolone	Salmonella	> 0,06	> 0,06	0,015-8 (10)
		E, coli	> 0,06	> 0,5
Colistin	Polymyxin	Salmonella	NA	> 2	1-16 (5)
		E, coli	> 2	> 2
Gentamicin	Aminoglycoside	Salmonella	> 2	> 4	0,5-16 (6)
		E, coli	> 2	> 4
Meropenem	Carbapenem	Salmonella	> 0,125	> 8	0,03-16 (10)
		E, coli	> 0,125	> 8
Nalidixic acid	Quinolone	Salmonella	> 8	NA	4-64 (5)
		E, coli	> 8	NA
Sulfamethoxazole	Folate pathway antagonist	Salmonella	NA	NA	8-512 (7)
		E, coli	> 64	NA
Tetracycline	Tetracycline	Salmonella	> 8	NA	2-32 (5)
		E, coli	> 8	NA
Tigecycline	Glycylcycline	Salmonella	NA	NA	0,25-8 (6)
		E, coli	> 0,5	> 0,5
Trimethoprim	Folate pathway antagonist	Salmonella	> 2	> 4	0,25-16 (7)
		E, coli	> 2	> 4

Table 3

Panel of antimicrobial substances to be included in AMR monitoring, EUCAST interpretative thresholds for resistance and concentration ranges to be tested in C. jejuni and C. coli

NA: not available
Antimicrobial	Class of antimicrobial	Species	Interpretative thresholds of AMR (mg/L)		Range of concentrations (mg/L)(No of wells in brackets)
			ECOFF	Clinical breakpoint
Chloramphenicol	Phenicol	C. jejuni	> 16	NA	2-64 (6)
		C. coli	> 16	NA
Ciprofloxacin	Fluoroquinolone	C. jejuni	> 0,5	> 0,5	0,12-32 (9)
		C. coli	> 0,5	> 0,5
Ertapenem	Carbapenem	C. jejuni	NA	NA	0,125-4 (6)
		C. coli	NA	NA
Erythromycin	Macrolide	C. jejuni	> 4	> 4	1-512 (10)
		C. coli	> 8	> 8
Gentamicin	Aminoglycoside	C. jejuni	> 2	NA	0,25-16 (7)
		C. coli	> 2	NA
Tetracycline	Tetracycline	C. jejuni	> 1	> 2	0,5-64 (8)
		C. coli	> 2	> 2

Table 4

Panel of antimicrobial substances to be included in AMR monitoring, EUCAST thresholds for resistance and concentration ranges to be tested in E. faecalis and E. faecium

NA: not available
Antimicrobial	Class of antimicrobial	Species	Interpretative thresholds of AMR (mg/L)		Range of concentrations (mg/L)(No of wells in brackets)
			ECOFF	Clinical breakpoint
Ampicillin	Penicillin	E. faecalis	> 4	> 8	0,5-64 (8)
		E. faecium	> 4	> 8
Chloramphenicol	Phenicol	E. faecalis	> 32	NA	4-128 (6)
		E. faecium	> 32	NA
Ciprofloxacin	Fluoroquinolone	E. faecalis	> 4	> 4	0,12-16 (8)
		E. faecium	> 4	> 4
Daptomycin	Lipopeptide	E. faecalis	> 4	NA	0,25-32 (8)
		E. faecium	> 8	NA
Erythromycin	Macrolide	E. faecalis	> 4	NA	1-128 (8)
		E. faecium	> 4	NA
Gentamicin	Aminoglycoside	E. faecalis	> 64	NA	8-1 024 (8)
		E. faecium	> 32	NA
Linezolid	Oxazolidinone	E. faecalis	> 4	> 4	0,5-64 (8)
		E. faecium	> 4	> 4
Quinupristin/Dalfopristin	Streptogramin	E. faecalis	NA	NA	0,5-64 (8)
		E. faecium	NA	> 4
Teicoplanin	Glycopeptide	E. faecalis	> 2	> 2	0,5-64 (8)
		E. faecium	> 2	> 2
Tetracycline	Tetracycline	E. faecalis	> 4	NA	1-128 (8)
		E. faecium	> 4	NA
Tigecycline	Glycylcycline	E. faecalis	> 0,25	> 0,25	0,03-4 (8)
		E. faecium	> 0,25	> 0,25
Vancomycin	Glycopeptide	E. faecalis	> 4	> 4	1-128 (8)
		E. faecium	> 4	> 4