Cross-sectional surveillance reveals multidrug-resistant Shiga toxin-producing Escherichia coli in drinking water, highlighting critical sanitation and public health risks.
Key Points
To evaluate the prevalence, virulence traits, and antimicrobial resistance profiles of coliforms and Escherichia coli contaminating potable water sources.
Collected and tested 150 potable water samples (100 tap water and 50 well water) across five districts in Gharbia governorate, Egypt.
Isolated coliforms and Escherichia coli, screening for Shiga toxin-producing E. coli (STEC), multidrug resistance phenotypes, and extended-spectrum beta-lactamase (ESBL) genes.
Coliforms contaminated 52% of tap and 76% of well water samples, while E. coli was present in 16% of samples overall (15% tap, 18% well; 23.7% rural, 8.1% urban), with rural sources 3.5 times more likely to be contaminated than urban sources (P = 0.01).
Among recovered E. coli isolates, 33.3% (n=8) were STEC, 62.5% exhibited multidrug resistance, and 29.2% (n=7) harbored ESBL genes.
A total of 87.5% of STEC isolates were multidrug-resistant and carried ESBL genes, displaying significantly higher resistance across six antibiotic classes compared to non-STEC isolates.