Urban Wastewater as Environmental Reservoirs of Multidrug-resistance Enterobacteriaceae during the COVID-19 Pandemic in India

Secondary bacterial infections have been associated with COVID-19, leading to increased antibiotic consumption and exacerbating the phenomenon of antimicrobial resistance (AMR). The present study evaluated the prevalence of multidrug-resistant (MDR) Enterobacteriaceae (specifically Escherichia coli and Klebsiella pneumoniae) in wastewater collected from three different Western Uttar Pradesh (WUP) zones during the pandemic. A total of 150 isolates were identified both biochemically and using VITEK-2. Antibiotic susceptibility testing was achieved using the disc diffusion method. Of the 150 isolates, Escherichia Coli (E. coli) (62%) was the predominant bacterial species, followed by Klebsiella pneumoniae (K. pneumoniae) (24%), other Enterobacteriaceae (8%) and a mixed population of bacterial isolates (6%). Also, 74% of the isolates were resistant to one or more antibiotic classes. A high percentage of MDR was detected in E. coli (57.14%), followed by K. pneumoniae (28.57%). However, compared to E. coli, the MDR prevalence of K. pneumoniae in different zones was significant (p-value=0.0081). Of the total isolates, 79.3% were extended-spectrum beta-lactamases (ESBL)-producers. The resistance to ESBL in E. coli was higher than in K. pneumoniae. The highest resistance was observed against penicillin, cephalosporin, quinolone, and fluoroquinolone. Notably, two K. pneumoniae isolates and Pantoea agglomerans showed resistance to all antibiotics tested, including colistin. To our knowledge, this is the first study performed in the Indian WUP region during COVID-19. Resistance to colistin and the multidrug resistance observed in the current study is a cause for concern due to the constant exposure of people to polluted waters in India, especially within resource-limited environments. The study calls for further studies to understand the full extent of the problem and implement mitigation measures.