Prevalence and diversity of antimicrobial resistant pathogens from medical and community wastewater in Dhaka City

Abstract

Background: Uncontrolled and excessive exposure of antibiotics in the medical waste poses a selective pressure to acquire and disseminate highly antibiotic resistance genes to common pathogenic bacteria. This study is aimed to isolate common pathogenic bacteria and prevalence of multiple drug resistance genes in community and hospital wastewater. Materials and Methods: Ten different wastewater samples (5 hospitals and 5 community wastewater) were aseptically collected and bacteriological investigations were performed for quantification and identification of bacterial isolates. Antibiotic susceptibility was performed by the Kirby-Bauer disk diffusion method and interpreted using the CLSI guideline. Polymerase chain-reaction (PCR) will be performed for identification of ESBL and carbapenem resistance genes. Results: Out of 234 isolates collected (based on different morphology); Gram-negative bacteria were predominant (85.04%). Top pathogenic-bacteria isolates were E.coli-(15%); Klebsiella pneumonia (12.82%); Pseudomonas aeruginosa (8.11%); Salmonella sp. (7.26%); Shigella sp. (6.84%); Staphylococcus aureus (6%). Overall 76.92% isolates were resistant to ampicillin and 34.61%, 40%, 23.08% and 12.39% were resistant to third-generation cephalosporin, vancomycin, colistin and carbapenem respectively. From overall isolates, the MDR and XDR organisms were found to be 84.62% and 5.13% respectively. PCR data on ESBL and carbapenem resistance genes are ongoing. Conclusion: High prevalence of multiple-drug-resistance bacteria in both hospital and community wastewater is indicating the dissemination of these pathogens in community which may lead to great public health issues if the situation is not tackled in near future.