Multiple Antimicrobial Resistance in Vibrio spp Isolated from River and Aquaculture Water Sources in Imo State, Nigeria

Aim: To study multiple antimicrobial resistances in Vibrio spp. isolated from river and aquaculture water sources in Imo State Nigeria.

Methodology: A total of 157 Vibrio isolates from river and aquaculture water sources were analysed for multiple antimicrobial resistance during a 6 month period. Antimicrobial resistance profile was determined by the Kirby-Bauer technique, while the phenotypic expression of β-lactamase production was performed by the double disk diffusion method. PCR was used to screen isolates for the presence of β-lactamase resistance genes.

Results: The isolates from river water expressed high resistance rates (81.3 to 97.8%) to the following antimicrobials: mezlocillin, doxycycline, tetracycline, carbenicillin and ampicillin, while resistance rate to kanamycin was moderate at 40.9%. Resistance rates for the aquaculture water Isolates were also high for the same antibiotics as the river water isolates, while resistance rate to kanamycin was low to moderate at 32.8%. Phenotypic screening of isolates for ESβL production showed the isolates were resistant to β-lactam antimicrobials and the β-lactamase inhibitor of amoxicillin/clavulnic acid combination. Gel electrophoresis of PCR products showed amplification for blaTEM of size 964bp.

Conclusion: Results showed the presence of highly resistant Vibrio isolates from the sampled environmental sources. The presence of resistance markers among the isolates in this study infers that they could be agents of transfer of resistance to other bacterial pathogens found in river and aquaculture water