Distribution of multiple β-lactam‑resistant and extended‑spectrum β-lactamases (ESBLs)-producing Escherichia coli in the Yamuna River flowing through Haryana, India.

The contamination of our natural rivers with multidrug-resistant (MDR) bacteria has emerged as a serious public health threat. In the present study, the prevalence of multiple β-lactam‑resistant Escherichia coli in the River Yamuna flowing through various districts of Haryana was evaluated. A total of 125 E. coli strains were isolated from selected sampling sites. A total of 22 isolates were found to be resistant to more than four β-lactam antibiotics and were considered multiple β-lactam-resistant E. coli isolates. Preliminary disc diffusion test for extended-spectrum β-lactamases (ESBLs) detection revealed 68.18% (15/22) of the isolates were presumptive ESBL producers, of which 27.27% (6/22) were confirmed ESBL producers by confirmatory E-Test. Molecular analysis for ESBL genes showed that 40.90% (9/22) isolates carried blaTEM gene, 27.27% (6/22) carried blaCTX-M gene while 4.54% (1/22) E. coli isolates harbour blaSHV gene. The Multiple Antibiotic Resistance index was found to be highest for isolates from Karnal (0.321) followed by Faridabad district (0.222), thereby indicating high antibiotic selective pressure and/or contamination at these sites. The present study aims to provide preliminary surveillance data on MDR isolates to support their effective management in natural water bodies.