Detection of multidrug resistance in Enterobacteriaceae in drinking water

Abstract

The rise of antibiotic resistance (AMR) and multidrug resistance (MDR) in the pathogenic Enterobacteriaceae family has become a major global concern in recent years. Waterborne infections still account for a significant mortality burden worldwide, especially within marginalised communities. Resistance, particularly in the case of Citrobacter species, has come into focus owing to their association with various nosocomial infections, UTIs, and opportunistic infections in immunocompromised patients. Herein, a study was conducted in marginalised areas during the monsoon season, involving the collection and analysis of drinking water samples from five different sites. The samples were analysed for enteric bacteria, among which Citrobacter coronae Tue2_1 was identified. This isolate was identified based on biochemical testing and genetic analysis involving 16S rDNA sequencing. The isolate was found to showcase MDR against beta-lactams, such as ampicillin and amoxiclav; macrolides such as azithromycin; and nitrofurantoin, a widely used nitrofuran. Intermediate resistance was also discovered against meropenem. This study identified resistance in a less-studied Citrobacter strain, highlighting the need to thoroughly monitor drinking water sources for their role as reservoirs of antimicrobial resistance.