Speaker
Description
Wastewater treatment plants (WWTPs) provide optimal conditions for the maintenance and spread of antibiotic-resistant bacteria. In this work, we describe the occurrence of antibiotic-resistant fecal coliforms in the inlet and the outlet of WWTPs in Settat City Morocco. This leads us to identify the role of WWTPs in the dissemination and the spread of antimicrobial-resistant Enterobacteriaceae in the environment. Raw and treated wastewater are received monthly from WWTPs of Settat. For each sample, we evaluated physicochemical parameters namely: T°, pH, Turbidity, TA, TAC, TH, conductivity, chloride, Nitrate, Nitrite, Sulphate, DCO, DBO5, and MES. Samples were used also to study indicators of fecal contamination, and the frequency of the resistant fecal coliforms community to aminoglycosides, beta-lactams, fluoroquinolones, carbapenems, polymyxins, and penicillins. For each sample, diluted aliquots of 100 mL were passed through membrane filters of 0.45um pore sizes. The resulting filters were placed into six modified Lactose-TTC-Agar mit Tergitol-7 (LTTC), this agar was supplemented with different concentrations of gentamicin, ciprofloxacin, ceftriaxone, colistin, imipenem, and ampicillin. After overnight incubation at 37°C, Matrix-assisted laser desorption/ionization-time of flight (MALDI) mass spectrometry (MS) MALDI-TOF MS was used to identify resistant isolates, and antimicrobial susceptibility testing was used too. In the community, we found an ampicillin-resistance rate of 42.1 % for fecal coliforms. Resistance rates to ciprofloxacin and colistin were 15 and 17.2%, respectively. However, the resistance rate has significantly increased between seasons to the third-generation cephalosporins (3GC). Our results indicate that the microbiological quality of the treated wastewater from WWTPs of Settat meets the Moroccan standards recommended for irrigation water. However, wastewater is routinely contaminated with multidrug-resistant enterobacteria. This is a concern for both public health and animal agriculture.
