Occurrence of Extended Spectrum Beta Lactamase (ESBL) Producers, Quinolone and Carbapenem Resistant Enterobacteriaceae Isolated from Environmental Samples along Msimbazi River Basin Ecosystem in Tanzania

Abstract

We conducted environmental surveillance of antimicrobial resistance (AMR) bacteria in the Msimbazi river basin in Tanzania to determine the occurrence of extended-spectrum β-lactamase (ESBL)-producing, carbapenem resistant <i>Enterobacteriaceae</i> (CRE) and quinolone resistant <i>Escherichia coli</i> and <i>Klebsiella</i> spp. A total of 213 <i>Enterobacteriaceae</i> isolates were recovered from 219 samples. Out of the recovered isolates, 45.5% (<i>n</i> = 97) were <i>Klebsiella pneumoniae</i> and 29.6% (<i>n</i> = 63) were <i>Escherichia coli</i>. <i>K. pneumoniae</i> isolates were more resistant in effluent (27.9%) compared to the <i>E. coli</i> (26.6%). The <i>E. coli</i> had a higher resistance in river water, sediment and crop soil than the <i>K. pneumoniae</i> (35 versus 25%), respectively. Higher resistance in <i>K. pneumoniae</i> was found in nalidixic acid (54.6%) and ciprofloxacin (33.3%) while the <i>E. coli</i> isolates were highly resistant to ciprofloxacin (39.7%) and trimethoprim/sulfamethoxazole (38%). Resistance increased from 28.3% in Kisarawe, where the river originates, to 59.9% in Jangwani (the middle section) and 66.7% in Upanga West, where the river enters the Indian Ocean. Out of 160 <i>E. coli</i> and <i>K. pneumoniae</i> isolates, 53.2% (<i>n</i> = 85) were resistant to more than three classes of the antibiotic tested, occurrence being higher among ESBL producers, quinolone resistant and carbapenem resistant strains. There is an urgent need to curb environmental contamination with antimicrobial agents in the Msimbazi Basin.