pathogens
3
.
1.6.5 Characterization of isolates
Characterization of foodborne bacterial isolates genus, species, and additional microbial subtyping is important but it depends on the capacity of the laboratory. If participating
laboratories do not have capacity for characterization of the isolates, they can send their isolates to a reference laboratory for characterization. Serotype information is fundamental to
understanding the epidemiology of Salmonella and its multidrug resistant isolates. However, not all laboratories would necessarily test for all possible serotypes of Salmonella. The most
common serotypes in a given area should be known in order to ensure an adequate supply of antisera 16. For epidemiological purposes, it may also be helpful to type the isolates using
molecular fingerprinting techniques such as PFGE, MLST or WGS. For antimicrobial resistant pathogens having public health implications, it would be helpful to have isolates characterized
for resistance mechanisms using PCRsequencing, WGS, etc.
1.7. Data management, validation, analysis and reporting
Reporting results from a programme of integrated surveillance of antimicrobial resistance in foodborne bacteria should include comprehensive analyses of surveillance data from all sources.
Rigorous, ongoing validation of laboratory and sample data is essential. On a routine basis, a joint evaluation of the data by surveillance system experts is recommended. Furthermore,
feedback on surveillance results should be solicited from microbiologists, epidemiologists, veterinarians, clinical practitioners and food scientists representing all sectors of the programme
of integrated surveillance of antimicrobial resistance in foodborne bacteria. Depending on the size of the programme of integrated surveillance of antimicrobial resistance in foodborne
bacteria, it can be advantageous to appoint a national coordinating body to audit and evaluate the integrated surveillance findings. The coordinating body should organize and direct the
analysis to help ensure that the integrated analysis, reporting and risk communication are done properly and in a timely manner. This group can also ensure that the programme continues to
meet the intended public health needs as outlined in the programme scope. They can also recommend modifications to address emerging issues. It is important that the data are analysed
with an emphasis on the human health significance of the findings. Surveillance results should be transparent and easily accessible. The results should also be communicated in language
that can be understood by non-specialists. It is helpful to compose narrative summaries, written in plain language, to accompany the data, in order to help consumers and other stakeholders
understand the risks, hazards, and meaning of significant or notable trends. The core of any programme of integrated surveillance of antimicrobial resistance in foodborne bacteria is an
isolate-level database containing relevant details of demographic epidemiological data and microbiological characteristics of samples. Data should be stored in a secure centralized
database that permits simple data entry and retrieval, as well as flexible reporting of standard and ad hoc analysis results. Compatibility with similar databases at the national and international
level facilitates collaboration among networks and systematic comparison of findings.
3 For pathogen-antimicrobial combinations selected by GLASS for global reporting of antimicrobial resistance in humans, see: www.who. intantimicrobial-resistancepublicationssurveillance-system-manualen
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Su rv
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Table 1.1 Suggested antimicrobials, by bacteria, for inclusion for antimicrobial susceptibility testing in a programme of integrated surveillance of antimicrobial resistance in foodborne
bacteria
i ii
iii iv
v vi
vii viii
ix x
xi Recommended antimicrobials used for sur veillance of Campylobacter jejuni and Campylobacter coli.
Cefepime is used in the European Union EU to distinguish bet ween AmpC and ESBL. Lincosamides are used in the treatment of some infections caused by Campylobacter.
Resistance towards er y thromycin reflects a zithromycin resistance. Nitrofurantoin is used in the United States of America for testing Gram-positive bacteria.
It is optional for Enterococcus to be tested for nitrofurantoin. Temocillin is included as a marker to detect the bla
OX A-48
genot ype. To screen for ciprofloxacin resistance in Salmonella spp. when disk dif fusion is used.
Nalidixic acid is used in Campylobacter to identif y rare mutations. Trimethoprim-sulfamethoxa zole can be used instead of using sulfisoxa zole or trimethoprim alone.
Dox ycycline may be used instead of tetracycline. Salmonella, E. coli
Gentamicin Chloramphenicol
Imipenem Meropenem
Cefoxitin Cefatoxime
or Ceftriaxone Ceftazidime
Cefepime
ii
Tigecycline
Azithromycin Nitrofurantoin
v
Ampicillin Amoxicillin
Temocillin
vii
Colistin Ciproloxacin
Nalidixic acid Peloxacin
viii
Sulisoxazole
x
Tetracycline Trimethoprim
Campylobacter
i
Gentamicin Streptomycin
Clindamycin
iii
Erythromycin
iv
Ampicillin
Ciproloxacin Nalidixic acid
ix
Tetracycline
xi
Enterococcus Gentamicin
Streptomycin Chloramphenicol
Vancomycin Teicoplanin
Tigecycline Daptomycin
Erythromycin Nitrofurantoin
vi
Ampicillin
Ciproloxacin
Quinupristin-dalfopristin Tetracycline
Staphylococcus Gentamicin
Chloramphenicol Cefoxitin
Vancomycin
Clindamycin Erythromycin
Linezolid Penicillin
Oxacillin Ciproloxacin
Rifampicin Quinupristin-dalfopristin
Sulisoxazole Tetracycline
Trimethoprim Antimicrobial classes
Aminoglycosides Amphenicols
Carbapenems Cephalosporins II
Cephalosporins III Cephalosporins IV
Glycopeptides Glycylcyclines
Lincosamides Lipopeptides
Macrolides Nitrofurans
Oxazolidinones Penicillins
Polymyxins Quinolones
Rifamycins Streptogramins
Sulfonamides
x
Tetracyclines Trimethoprim
x
Antimicrobials italicized are second priorit y.
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