Incidence and transferability of antibiotic resistance in the enteric bacteria isolated from hospital wastewater

Abstract

This study reports the occurrence of antibiotic resistance and production of β-lactamases including extended spectrum beta-lactamases (ESβL) in enteric bacteria isolated from hospital wastewater. Among sixty-nine isolates, tested for antibiotic sensitivity, 73.9% strains were resistant to ampicillin followed by nalidixic acid (72.5%), penicillin (63.8%), co-trimoxazole (55.1%), norfloxacin (53.6%), methicillin (52.7%), cefuroxime (39.1%), cefotaxime (23.2%) and cefixime (20.3%). Resistance to streptomycin, chloramphenicol, nitrofurantoin, tetracycline, and doxycycline was recorded in less than 13% of the strains. The minimum inhibitory concentration (MIC) showed a high level of resistance (800–1600 μg/mL) to one or more antibiotics. Sixty three (91%) isolates produced β-lactamases as determined by rapid iodometric test. Multiple antibiotic resistances were noted in both among ESβL and non-ESβL producers. The β-lactamases hydrolyzed multiple substrates including penicillin (78.8% isolates), ampicillin (62.3%), cefodroxil (52.2%), cefotoxime (21.7%) and cefuroxime (18.8%). Fifteen isolates producing ESβLs were found multidrug resistant. Four ESβL producing isolates could transfer their R-plasmid to the recipient strain E. coli K-12 with conjugation frequency ranging from 7.0 × 10−3 to 8.8 × 10−4. The findings indicated that ESβL producing enteric bacteria are common in the waste water. Such isolates may disseminate the multiple antibiotic resistance traits among bacterial community through genetic exchange mechanisms and thus requires immediate attention.

Microbial Community Composition and Antibiotic Resistance Genes within a North Carolina Urban Water System

“…Surface waters in areas devoid of anthropogenic involvement are known to lack most antibiotic resistance markers, including many mobile elements [68,69]; however, some resistance factors do emerge naturally through the process of recombination and mutation [68], and the conditions with the potential to exacerbate this process do exist in Charlotte's urban streams [70]. Given the tendency of environmental resistance factors to be passed to clinical pathogens [71,72], further study of the impact of maintaining permanent low concentrations of antibiotics in the stream, in the presence of resistance elements from wastewater or environmental sources, is critical for understanding how we can improve water treatment to safeguard both the ecosystem and human health.…”

Antibiotic Resistance and Antibiotic Resistance Genes in Escherichia coli Isolates from Hospital Wastewater in Vietnam

“…Previous reports show comparatively lower prevalence rates. In 2004–2005, an Indian study indicated that 55% of enteric bacteria found in hospital wastewater were resistant to co-trimoxazole [ 23 ]. A study from Poland showed that 20% of E. coli isolates from hospital wastewater collected before 2013 were resistant to co-trimoxazole [ 24 ].…”

Antibiotic Susceptibilities of Enterococcus Species Isolated from Hospital and Domestic Wastewater Effluents in Alice, Eastern Cape Province of South Africa

“…Hospitals and clinics are major reservoirs for large numbers of pathogenic bacteria comprised of resident and community introduced strains [ 1 ]. High usage of antibiotics to treat infections in patients serves as a selective pressure for resistance development and there are concerns with transmission and their long term survival in the environment [ 2 ]. Dissemination of antibiotic resistant bacteria (ARB) from hospitals can occur via various routes such as hospital wastewater, discharged patients and health care workers [ 2 , 3 ].…”

“…High usage of antibiotics to treat infections in patients serves as a selective pressure for resistance development and there are concerns with transmission and their long term survival in the environment [ 2 ]. Dissemination of antibiotic resistant bacteria (ARB) from hospitals can occur via various routes such as hospital wastewater, discharged patients and health care workers [ 2 , 3 ]. Antibiotics in wastewater can arise from excretion in urine and faces, direct disposal of expired drugs, and accidental spilling; these events could serve as additional selective pressure on bacteria while in wastewater.…”