Bacteriological study of Payra river: microbial isolation, identification, analysis of antimicrobial resistance and pathogenicity

Abstract

"Introduction: Water is the most precious element for all living creatures, being used for drinking, bathing, domestic purposes, etc. Being a riverine country, Bangladesh's people depend heavily on river water. This causes the water to be contaminated in various ways that raise serious public health concerns in terms of infection from antibiotic-resistant bacteria.

Methodology: 21 samples were collected from 7 sampling sites in Patuakhali and processed within 24 hours of collection. The samples were spread on several selective media: following which 47 isolates were selected based on distinct morphologies. Several biochemical tests were employed for initial identification, after which antibiotic susceptibility against Amikacin, Amoxicillin, Amoxyclav, Azithromycin, Cefixime, Ceftriaxone, Colistin, Erythromycin, Levofloxacin, Meropenem, Penicillin, Tetracycline, and Vancomycin was examined. DNAse and coagulase tests were investigated to determine the extent of pathogenicity.

Results: In this study, out of 47 isolates, Staphylococcus spp was the most predominant (20%) in the water samples, followed by Escherichia coli (16%), and Bacillus spp. (14%). Among the isolates, 51% and 68% were proven to be coagulase and DNase positive respectively, confirming the pathogenicity of our organisms. 94% of the isolates were penicillin-resistant followed by 73% amoxiclav-resistant. However, 100% and 95% of the isolates were susceptible to meropenem and levofloxacin respectively.

Conclusion: The results from our study form the baseline data for the bacteriology of Payra river which emphasizes the presence of enteric coliforms, especially Escherichia coli followed by Serratia spp., Streptococcus spp, Salmonella spp., Klebsiella spp., Enterococcus spp.,. and Pseudomonas aeuruginosa. Pathogenic strains were detected which increase the risk of infections. In addition, the high rate of DNAse and Coagulase positive isolates shows the extent of contamination which can spread several diseases among the dwellers who use water from this river."