Phylotyping, Pathotyping and Phenotypic Characteristics of Escherichia coli Isolated from Various Street Foods in Bangladesh

Abstract

The burden of street food contamination remains significantly higher among developing countries, making its consumers' health compromised. This study aimed at identifying Escherichia coli in local street foods, track their sources and characterize their virulence properties, antimicrobial susceptibility patterns, and incidence of recent fecal contamination. Twelve E. coli isolates isolated from 28 types of street foods sold at different locations of Dhaka metropolitan city were confirmed by both culture-based and molecular methods. Phylogroup B1 of environment origin was the most predominant (58%, n=12) among the isolates, followed by commensal phylogroup A (16%), phylogroup C (8%), D (8%), and E (8%). Alarmingly, 8% of the isolates were confirmed to be Enteropathogenic E. coli (EPEC), harboring hlyA gene, and 41% were due to recent fecal contamination cases confirmed by the presence of the eae gene. Isolates showed the highest resistance to ampicillin, followed by chloramphenicol. However, resistance could not be correlated to the presence of class 1 integron as isolates sensitive to these antibiotics also harbored this mobile genetic element. The findings of this study demonstrated the presence of antibiotic-resistant, potentially pathogenic E. coli in street food which emphasizes the health hazard associated with consumption of such foods.