Assessment of the viability of 3rd generation cephalosporin-resistant enterobacterial cells during transport under different storage conditions

Yanet López-Dorta, Michel Báez-Arias, Rosa Elena Hernández-Fillor, Ivette Espinosa-Castaño


Antimicrobial resistance (AMR) is a growing threat to public and animal health. Monitoring is fundamental in terms of obtaining, compiling and exchanging data and carrying out interventions. The efficient transport of samples is an essential part of the epidemiological research and diagnostic laboratory. The objective of this study was to assess the viability of two 3rd generation cephalosporin-resistant enterobacterial species under different storage conditions for detection of antimicrobial resistance. The preliminary study was based on the principles of the qualitative method published by the CLSI (M-40A2). Swabs were introduced in tubes containing different loads of target microorganisms (Extended spectrum beta-lactamase-producing Escherichia coli and third generation cephalosporin-resistance Salmonella enterica, clinical isolate), subsequently placed in Cary-Blair transport medium andpreserved at room temperature (28-32°C) and under refrigerated conditions (4-8°C), during 24 and 48 hrs. The results showed recovery for all microorganism / dilution / temperature combinations at 24 and 48 hours, being the refrigerated transport during 24 hours the most appropriate for the storage, preserving initial load of each bacteria. However at room temperature, it is not recommended to keep the samples due to the observed overgrowth.

Palabras clave

antimicrobial resistance; enterobacteria; samples; transport


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