Epidemiological cut-off values for Vibrio anguillarum MIC and disc diffusion data generated by standardised methods
Investigation article published in Diseases of Aquatic Organisms
August 31st, 2023
This work aims to generate the data needed to set epidemiological cut-off values for minimum inhibitory concentration (MIC) and disc-diffusion zone measurements of Vibrio anguillarum. A total of 261 unique isolates were tested, applying standard methods specifying incubation at 28°C for 24-28 h. Aggregated MIC distributions for a total of 247 isolates were determined in 9 laboratories for 11 agents. Data aggregations of the disc zone for the 10 agents analysed contained between 157 and 218 observations made by 4 to 7 laboratories. Acceptable ranges for quality control (QC) reference strains were available for 7 agents and the related multi-laboratory aggregated data were censored, excluding the data of a laboratory that failed to meet QC requirements. Statistical methods were applied to calculate epidemiological cut-off values. Cut-off values for MIC data were calculated for florfenicol (≤1 µg ml-1), gentamicin (≤4 µg ml-1), oxytetracycline (≤0.25 µg ml-1) and trimethoprim/sulfamethoxazole (≤0.125/2.38 µg ml-1). The cut-off values for disc zone data were calculated for enrofloxacin (≥29 mm), florfenicol (≥27 mm), gentamicin (≥19 mm), oxolinic acid (≥24 mm), oxytetracycline (≥24 mm) and trimethoprim/sulfamethoxazole (≥26 mm). MIC and disc-diffusion zone data for the other agents where not supported by QC, thus yielding only provisional cut-off values (meropenem, ceftazidime). Regardless of whether QC is available, some of the aggregated MIC distributions (enrofloxacin, oxolinic acid), disc zone (sulfamethoxazole), and MIC and disc-diffusion distributions (ampicillin, chloramphenicol) did not meet the statistical requirements. The data produced will be submitted to the Clinical Laboratory Standards Institute for their consideration in setting international consensus epidemiological cut-off values
Smith P., Le Devendec L., Jouy E., Larvor E., Le Breton A., Picon-Camacho S., Zrncic S., Zupicic IG., Oraic D., Karatas S., Verner-Jeffreys D., Wokorac-Joseph A., Light E., van Essen-Zanbergen A., van Gelderen B., Voobergen-Laarman M., Haenen OLM., Veldman KT., Madsen L., Mouritsen KK., Smith-Svanevik C., Hakonsholm F., Vela AI., Garcia M., Florio D., Fioravanti M., Cortinovis L., Pretto T., Manfrin A. and Baron S.
 | School of Natural Science. National University of Ireland Galway (NUIG). |
 | Mycoplasmology-Bacteriology-Antibioresistance Unit. Ploufragan Plouzané Laboratory. Agence Nationale de Sécurité Sanitaire de l´alimentation, de l´environnement et du travail (ANSES). |
| Vet’eau- Selarl du Dr Alain Le Breton. | |
| Laboratory for Fish and Molluscs Diseases. Croatian Veterinary Institute. | |
| Faculty of Aquatic Sciences. Istanbul University-Cerrahpasa. | |
| Centre for Environment. Fisheries and Aquaculture Science. | |
| UK FAO Reference Centre for AMR. | |
| Veterinary Medicines Directorate (VMD). | |
| Wageningen Bioveterinary Research. | |
 | Section for Fish and Shellfish Diseases. National Institute of Aquatic Resources. Technical University of Denmark (DTU). |
| Department of Contaminants and Biohazards. Institute of Marine Research. | |
 | Servicio de Identificación y Caracterización Microbiana (ICM). Centro de Vigilancia Sanitaria Veterinaria (VISAVET). Universidad Complutense (UCM). |
| Departamento de Sanidad Animal. Facultad de Veterinaria. Universidad Complutense (UCM). |
| Department of Veterinary Medical Sciences. Università di Bologna (UNIBO). | |
| Fish Pathology Unit. Istituto Zooprofilattico Sperimentale delle Venezie. | |
