Publication Abstract

High prevalence of multidrug-tolerant bacteria and associated antimicrobial resistance genes isolated from ornamental fish and their carriage water

Multidrug-tolerance and associated antimicrobial resistance genes in bacteria isolated from ornamental fish and their carriage water.

Background: Antimicrobials are used to directly control bacterial infections in pet (ornamental) fish and are routinely addedto the water these fish are shipped in to suppress the growth of potential pathogens during transport.

Methodology/Principal Findings: To assess the potential effects of this sustained selection pressure, 127 Aeromonas spp. isolated from warm and cold water ornamental fish species were screened for tolerance to 34 antimicrobials. Representative isolates were also examined for the presence of 54 resistance genes by a combination of miniaturized microarray and conventional PCR. Forty-seven of 94 Aeromonas spp. isolates recovered from tropical ornamental fish and their carriage water were tolerant to at least 15 antibiotics, representing seven or more different classes of antimicrobial. The quinolone and fluoroquinolone resistance gene, qnrS2, was detected at high frequency (37% tested recent isolates were positive by PCR). Class 1 integrons, IncA/C broad host range plasmids and a range of other antibiotic resistance genes, including floR, blaTEM21, tet(A), tet(D), tet(E), qacE2, sul1, and a number of different dihydrofolate reductase and aminoglycoside transferase coding genes were also detected in carriage water samples and bacterial isolates.

Conclusions: These data suggest that ornamental fish and their carriage water act as a reservoir for both multi-resistantbacteria and resistance genes

Reference:

D. Verner-Jeffreys*, T. Welch, T. Schwarz*, M.J. Pond*, M.J.Woodward, S. J. Haig*, G. Rimmer*, V. Morrison and C. Baker-Austin*. (2009) Multidrug-tolerance and associated antimicrobial resistance genes in bacteria isolated from ornamental fish and their carriage water. PLoS ONE 4(12): e8388.

D. Verner-Jeffreys*, T. Welch, T. Schwarz*, M.J. Pond*, M.J.Woodward, S. J. Haig*, G. Rimmer*, V. Morrison and C. Baker-Austin*.

PLoS ONE 4(12): e8388.