Establishing Streptomycin Epidemiological Cut-Off Values for Salmonella and Escherichia coli
Investigación publicada en Microbial Drug Resistance (Larchmont, N.Y.)
1 de febrero de 2012
This study was conducted to elucidate the accuracy of the current streptomycin epidemiological cut-off value (ECOFF) for Escherichia coli and Salmonella spp. A total of 236 Salmonella enterica and 208 E. coli isolates exhibiting MICs between 4 and 32 mg/L were selected from 12 countries. Isolates were investigated by polymerase chain reaction for aadA, strA, and strB streptomycin resistance genes. Out of 236 Salmonella isolates, 32 (13.5%) yielded amplicons for aadA (n = 23), strA (n = 9), and strB (n = 11). None of the 60 Salmonella isolates exhibiting MIC 4 mg/L harbored resistance genes. Of the Salmonella isolates exhibiting MICs 8 mg/L, 16 mg/L, and 32 mg/L, 1.6%, 15%, and 39%, respectively, tested positive for one or more genes. For most monitoring programs, the streptomycin ECOFF for Salmonella is wild type (WT) ≤32 or ≤16 mg/L. A cut-off value of WT ≤32 mg/L would have misclassified 13.5% of the strains as belonging to the WT population, since this proportion of strains harbored resistance genes and exhibited MICs ≤32 mg/L. Out of 208 E. coli strains, 80 (38.5%) tested positive for aadA (n = 69), strA (n = 18), and strB (n = 31). Of the E. coli isolates exhibiting MICs of 4 mg/L, 8 mg/L, 16 mg/L, and 32 mg/L, 3.6%, 17.6%, 53%, and 82.3%, respectively, harbored any of the three genes. Based on the European Committee on Antimicrobial Susceptibility Testing guidelines (ECOFF ≤16 mg/L), 25% of the E. coli strains presenting MIC ≤16 mg/L would have been incorrectly categorized as belonging to the WT population. The authors recommend an ECOFF value of WT ≤16 mg/L for Salmonella and WT ≤8 mg/L for E. coli
Garcia-Migura L., Sunde M., Karlsmose S., Veldman K., Schroeter A., Guerra B., Granier SA., Perrin-Guyomard A., Gicquel-Bruneau M., Franco A., Englund S., Teale C., Heiska H., Clemente L., Boerlin P., Moreno MA., Daignault D., Mevius DJ., Hendriksen RS. y Aarestrup F.
Servicio de Zoonosis de Transmisión Alimentaria y Resistencia a Antimicrobianos (ZTA). Centro de Vigilancia Sanitaria Veterinaria (VISAVET). Universidad Complutense (UCM). | |
Departamento de Sanidad Animal. Facultad de Veterinaria. Universidad Complutense (UCM). | |
National Food Institute (DTU Food). Technical University of Denmark (DTU). | |
Seksjon for Bakteriologi. Veterinærinstituttet. | |
Central Veterinary Institute. Wageningen University (UR). | |
Federal Institute for Risk Assessment (BfR). | |
Agence Nationale de Sécurité Sanitaire de l´alimentation, de l´environnement et du travail (ANSES). | |
AFSSA—LERMVD. | |
Istituto Zooprofilattico Sperimentale delle Regioni Lazio e Toscana (IZSLT). | |
Department of Animal Health and Antimicrobial Strategies. National Veterinary Institute (SVA). | |
Veterinary Laboratories Agency. Department for Environment, Food and Rural Affairs (Defra). | |
Finnish Food Safety Authority (EVIRA). | |
Laboratório Nacional de Investigação Veterinária (LNIV). Instituto Nacional de Recursos Biologicos (INRB). | |
Ontario Veterinary College. University of Guelph. | |
Laboratory for Foodborne Zoonoses. Public Health Agency of Canada (PHAC). | |