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

Abstract

The environmental spread of antibiotic-resistant bacteria has been recognised as a growing public health threat for which hospitals play a significant role. The aims of this study were to investigate the prevalence of antibiotic resistance and antibiotic resistance genes (ARGs) in Escherichia coli isolates from hospital wastewater in Vietnam. Wastewater samples before and after treatment were collected using continuous sampling every month over a year. Standard disk diffusion and E-test were used for antibiotic susceptibility testing. Extended-spectrum beta-lactamase (ESBL) production was tested using combined disk diffusion. ARGs were detected by polymerase chain reactions. Resistance to at least one antibiotic was detected in 83% of isolates; multidrug resistance was found in 32%. The highest resistance prevalence was found for co-trimoxazole (70%) and the lowest for imipenem (1%). Forty-three percent of isolates were ESBL-producing, with the blaTEM gene being more common than blaCTX-M. Co-harbouring of the blaCTX-M, blaTEM and qepA genes was found in 46% of isolates resistant to ciprofloxacin. The large presence of antibiotic-resistant E. coli isolates combined with ARGs in hospital wastewater, even post-treatment, poses a threat to public health. It highlights the need to develop effective processes for hospital wastewater treatment plants to eliminate antibiotic resistant bacteria and ARGs.

The Antibiotic Resistance Profiles of Escherichia Coli Isolated from Pre and Post Treated Hospital Sewage

“…The rate of ESBL-producing E.coli strains have been reported higher than our results which may re ect difference in the regional frequencies of resistance genes (7,21). In the present study, the rate of ESBL-producing E. coli strains was slightly higher in the post treatment sewage isolates, which may re ect the transferring of EBSL among bacteria within sewage.…”

“…The resistance rate of ESBL-producing isolates to most antibiotics tested was slightly lower in post sewage treatment isolates; however, the resistance rate in non-ESBL isolates for most antibiotics was higher in post treated isolates. It has been shown that in many cases, sewage treatment process cannot signi cantly eliminate resistant strains or resistance genes (7). Furthermore, there are some reports that showed the increase in both antibiotic resistance rates and antibiotic resistance genes for post treatment sewage isolates (18,19).…”

“…Acquired resistance to beta-lactams is mainly attained by the Extendedspectrum beta-lactamases (ESBL) in E.coli (6). The bla CTX-M, bla TEM, and bla SHV are the most common types of ESBLs that have been reported in bacteria isolated from hospital sewage (7). The TEM and SHV beta-lactamases, by hydrolysis the molecules of beta-lactam antibiotics, make them inactive.…”

“…Since the hospital sewage is an important source of spreading the resistant strains of E. coli to environment, the effective treatment of hospital sewage is important to eliminate these resistant strains (7). The aim of this study was to evaluate the antibiotic resistance and some common resistance genes of E. coli isolated from hospital sewage before and after treatment.…”

Detection of Multidrug-Resistance Gram-Negative Bacteria from Hospital Sewage in North East, Nigeria

“…Profiles of bacterial population in different environments have been reported worldwide. In addition, the resistance profiles of such bacteria have been studied [30][31][32][33][34]. This study focuses to investigate the members of gram-negative bacteria from hospital sewage and their resistance profile to the most commonly used antibiotics in the study area.…”