Antimicrobial Resistance and β-Lactamase Production in Clinically Significant Gram-Negative Bacteria Isolated from Hospital and Municipal Wastewater

Abstract

Hospital and municipal wastewater contribute to the spread of antibiotic-resistant bacteria and genes in the environment. This study aimed to examine the antibiotic resistance and β-lactamase production in clinically significant Gram-negative bacteria isolated from hospital and municipal wastewater. The susceptibility of bacteria to antibiotics was tested using the disk diffusion method, and the presence of extended-spectrum β-lactamases (ESBL) and carbapenemases was determined using an enzyme inhibitor and standard multiplex PCR. Analysis of antimicrobial resistance of total bacterial strains (n = 23) revealed that most of them were resistant to cefotaxime (69.56%), imipenem (43.47%), meropenem (47.82%) and amoxicillin-clavulanate (43.47%), gentamicin (39.13%), cefepime and ciprofloxacin (34.78%), trimethoprim-sulfamethoxazole (30.43%). A total of 8 of 11 phenotypically confirmed isolates were found to have ESBL genes. The blaTEM gene was present in 2 of the isolates, while the blaSHV gene was found in 2 of the isolates. Furthermore, the blaCTX-M gene was found in 3 of the isolates. In one isolate, both the blaTEM and blaSHV genes were identified. Furthermore, of the 9 isolates that have been phenotypically confirmed to have carbapenemase, 3 were confirmed by PCR. Specifically, 2 isolates have the blaOXA-48 type gene and 1 have the blaNDM-1 gene. In conclusion, our investigation shows that there is a significant rate of bacteria that produce ESBL and carbapenemase, which can promote the spread of bacterial resistance. Identifying ESBL and carbapenemase production genes in wastewater samples and their resistance patterns can provide valuable data and guide the development of pathogen management strategies that could potentially help reduce the occurrence of multidrug resistance.

Occurrence and characterization of β-lactamase-producing bacteria in biomedical wastewater and in silico enhancement of antibiotic efficacy

“…This phenomenon seriously affects public health, as it limits the treatment options available to medical professionals and increases the risk of infections becoming untreatable. Identifying the presence and understanding of the characteristics of pathogenic bacteria producing β-lactamase in hospital wastewater is of utmost importance to develop effective strategies for combating antibiotic resistance and safeguarding public health ( Muteeb et al, 2022a ; Irfan et al, 2023 ).…”

Hospital Wastes as Potential Sources for Multi-Drug-Resistant ESBL-Producing Bacteria at a Tertiary Hospital in Ethiopia

“…This phenomenon has resulted in increased rates of morbidity, mortality, and escalated healthcare expenditures [1,2]. The presence of these bacteria in healthcare facilities and their surroundings further exacerbates the problem [3]. Contaminated surfaces, hospital sewage, and other environmental factors within the hospital have been identified as potential reservoirs and sources of MDR bacteria due to their close proximity to patients and healthcare workers.…”

“…Contaminated surfaces, hospital sewage, and other environmental factors within the hospital have been identified as potential reservoirs and sources of MDR bacteria due to their close proximity to patients and healthcare workers. Furthermore, houseflies have the potential to mechanically transmit MDR bacteria to both patients and the wider community [3][4][5]. In resource-limited settings like Ethiopia, where healthcare infrastructure and waste management systems are suboptimal, the risk posed by hospital waste as a reservoir for MDR bacteria is becoming a pressing concern [1,6].…”