Search

Beta-lactamase-producing Enterobacterales bacteria cause severe hard-to-treat infections. Currently, they are spreading beyond hospitals and becoming a serious global health concern. This study investigated the prevalence and molecular characterization of extended-spectrum ß-lactamase and AmpC-type ß-lactamase-producing Enterobacterales (ESBL-PE, AmpC-PE) in wastewater from livestock and poultry slaughterhouses in Ardabil, Iran. A total of 80 Enterobacterales bacteria belonging to 9 species were identified. Among the isolates, Escherichia coli (n = 21/80; 26.2%) and Citrobacter spp. (n = 18/80; 22.5%) exhibited the highest frequency. Overall, 18.7% (n = 15/80) and 2.5% (n = 2/80) of Enterobacterales were found to be ESBL and AmpC producers, respectively. The most common ESBL producer isolates were E. coli (n = 9/21; 42.8%) and Klebsiella pneumoniae (n = 6/7; 85.7%). All AmpC-PE isolates belonged to E. coli strains (n = 2/21; 9.5%). In this study, 80% of ESBL-PE and 100% of AmpC-PE isolates were recovered from poultry slaughterhouse wastewater. All ESBL-PE and AmpC-PE isolates were multidrug-resistant. In total, 93.3% of ESBL-PE isolates harbored the blaCTX-M gene, with the blaCTX-M-15 being the most common subgroup. The emergence of ESBL-PE and AmpC-PE in wastewater of food-producing animals allows for zoonotic transmission to humans through contaminated food products and contaminations of the environment. [ABSTRACT FROM AUTHOR]

Background & Objective: Staphylococcus aureus causes various hospital- and community-acquired infections. This study aimed to investigate the phenotypic and genotypic characteristics of erythromycin and inducible clindamycin resistance, virulence gene profiles, and spa types of S. aureus isolates collected from patients in Ardabil Province, Iran. Methods: A total of 118 clinical S. aureus isolates, including 50 (42.4%) methicillinresistant S. aureus (MRSA) and 68 (57.6%) methicillin-susceptible S. aureus (MSSA) strains, were investigated. Resistance patterns were determined by the disk diffusion method and minimum inhibitory concentration (MIC) test. Inducible macrolidelincosamide- streptogramin B (iMLSB) resistance was detected using D-test method. The polymerase chain reaction (PCR) was used to identify the virulence and resistanceencoding genes. Additionally, the spa types of the isolates were determined using the PCR, followed by sequencing. Results: In total, 49.1% (58/118) and 44% (52/118) of the isolates were resistant to erythromycin and clindamycin, respectively. Overall, 13.5% (16/118) of the isolates showed the iMLSB resistance phenotype. The ermC gene (72.4% [42]) was the most frequent erythromycin resistance-encoding gene, followed by ermA (60.3% [35]), ermB (60.3% [35]), ermTR (51.7% [30]), and msrA (15.5% [9]) genes among erythromycinresistant isolates. The virulence genes hla, hld, sea, LukS PV, tst, seb, sed, eta, sec, and etb were detected in 93.2%, 74.5%, 70.3%, 32.2%, 29.6%, 17%, 8.5%, 8.5%, 5.9%, and 4.2% of the isolates, respectively. Ten different spa types were identified for 58 erythromycin-resistant S. aureus strains, of which t030 and t078 types were the most common types. Conclusion: A high frequency of macrolide- and lincosamide-resistant S. aureus isolates with different genetic backgrounds of resistance and virulence may be found in patients in Ardabil Province, Iran. [ABSTRACT FROM AUTHOR]

Hospital wastewater can contaminate the environment with antibiotic-resistant and virulent bacteria. We analyzed wastewater samples from four hospitals in Ardabil province, Iran for Enterococcus faecium and Enterococcus faecalis using culture and molecular methods. We also performed antimicrobial susceptibility testing and polymerase chain reaction testing for resistance and virulence genes. Out of 141 enterococci isolates, 68.8% were E. faecium and 23.4% were E. faecalis. Ciprofloxacin and rifampicin showed the highest level of resistance against E. faecalis and E. faecium isolates at 65%. High-level gentamicin resistance (HLGR), high-level streptomycin resistance (HLSR), ampicillin, and vancomycin resistance were observed in 25, 5, 10, and 5.15% of E. faecium, and 15, 6, 15, and 3.03% of E. faecalis isolates, respectively. The ant(60 )-Ia and ant(30 )-Ia genes that were responsible for streptomycin resistance were observed in HLSR isolates and aph(30 )-IIIa and aac(60 ) Ieaph(2″)-Ia genes accounting for gentamicin resistance were detected in HLGR isolates. vanA was the predominant gene detected in vancomycin-resistant isolates. The majority of isolates were positive for gelE, asa1, esp, cylA, and hyl virulence genes. We found that drug-resistant and virulent E. faecalis and E. faecium isolates were prevalent in hospital wastewater. Proper treatment strategies are required to prevent their dissemination into the environment. [ABSTRACT FROM AUTHOR]

Background and Objectives: he occurrence and characteristics of Extended Spectrum- and AmpC-ß-lactamase producing Enterobacterales (ESBL-PE and AmpC-PE) in an urban wastewater treatment plant (WWTP) were investigated. Materials and Methods: A total of 30 wastewater samples were collected from all sections of WWTP. Enterobacterales were isolated and identified using standard microbiological tests. The antibiotic resistance profile was determined by the Kirby-Bauer disk diffusion method. Phenotypic screening for ESBL-PE and AmpC-PE isolates was performed by double-disk synergy and boronic acid disk potentiation tests, respectively. The isolates were examined for AmpC- and ESBL-encoding genes by PCR and sequencing methods. Results: Among 146 Enterobacterales isolates, 8.9% (n=13) [ESBL-only; 5.48% (n=8) and ESBL + AmpC; 3.42% (n=5)] were ESBL-producers and 15.75% (n=23) [AmpC-only; 12.33% (n=18) and ESBL + AmpC; 3.42% (n=5)] AmpC-producers. Hafnia spp. with 33.33% (n=1/3) and E. coli with 20.58% (n=7/34) [ESBL-only; 17.64% (n=6/34) and ESBL + AmpC; 2.94% (n=1/34)] were the most common ESBL-producing bacteria. Enterobacter spp. with 37.50% (n=6/16) of isolates were the most common AmpC-producing organisms. ESBL- and/or AmpC-producing isolates were identified in all parts of the WWTP including 80% (n=8/10) of samples taken from effluent. Among ESBL-producing isolates, blaCTX-M TEM, and blaSHV ESBL-encoding genes were found in 61.5% (n=8), 15.3% (n=2), and 7.7% (n=1) of isolates, respectively. All CTX-Mtype enzymes belonged to the CTX-M-1 group and CTX-M-15 subgroup. blaTEM and blaSHV type genes belonged to blaTEM-20 and blaHSV-12 subtypes, respectively. bla with 73.9% (n=17/23), and blaCIT and bla with 30.4% (n=7/23) each, were the most common AmpC-encoding genes among AmpC-producing isolates. Overall, 75% of ESBL-producing and 55.5% of AmpC-producing isolates exhibited multi-drug resistance phenotypes. The organisms were most resistant against ampicillin (82.2%) nalidixic acid (43.8%) and cephalexin (41.1%). Conclusion: ESBL- and AmpC-producing Enterobacterales spp. with diverse genetic resistance backgrounds in WWTP effluent poses a significant risk to public health. [ABSTRACT FROM AUTHOR]