DAO prepress abstract   -  DOI: https://doi.org/10.3354/dao03766

ABSTRACT: This work generates the data needed to set epidemiological cut-off values for disc-diffusion zone measurements of Vibrio cholerae. The susceptibility of 147 European isolates of non-O1/non-O139 Vibrio cholerae to nineteen antibiotics was established using a standardised disc diffusion method which specified incubation of Mueller Hinton agar plates at 35°C. Epidemiological cut-off values were calculated by analysis of the zone size data with the statistically based normalised resistance interpretation method. Cut-off values for seventeen agents were calculated by analysis of the aggregated data from all four laboratories participating in this study. The cut-off values calculated were ≥18 mm for amoxicillin-clavulanate, ≥18 mm for amikacin, ≥19 mm for ampicillin, ≥27 mm for cefepime, ≥31 mm for cefotaxime, ≥24 mm for ceftazidime, ≥24 mm for chloramphenicol, ≥31 mm for ciprofloxacin, ≥16 mm for erythromycin, ≥ 27 mm for florfenicol, ≥16 mm for gentamicin, ≥23 mm for imipenem, ≥25 mm for meropenem, ≥29 mm for nalidixic acid, ≥28 mm for norfloxacin, ≥13 mm for streptomycin and ≥23 mm for tetracycline. For the other two agents the data from one laboratory was excluded from the censored aggregation because the data from that laboratory was considered excessively imprecise. The cut-off values for these two agents calculated for the aggregation of the data from three laboratories were ≥23 mm for trimethoprim and ≥24 mm for trimethoprim-sulfamethoxazole. These zone size data will be submitted to CLSI and EUCAST for their consideration in setting international consensus epidemiological cut-off values for non O1/non-O139 Vibrio cholerae.