Abstract

A total of 60 diverse dairy product samples, including ice cream, Ras cheese, and Kariesh cheese (20 of each), were randomly collected from street vendors in different regions of Alexandria governorate, Egypt to investigate the prevalence of pathogenic E. coli. The outcomes revealed presumptive positive colonies of 83.33% and 80% in ice cream and Kariesh cheese samples, respectively. Confirmatory tests via conventional biochemical identification affirmed the presence of E. coli in 80% of the samples. However, Vitek 2 compact testing revealed that only 46.66% were positive, in contrast to PCR techniques, which substantiated a prevalence of E. coli in only 25% of the samples, with 35% in street-vended Ras cheese and 25% in Kariesh cheese. The phoA gene, integral to E. coli, was prominently featured in street-vended Ras cheese samples at a striking 100%, while the virulence genes stx1 and stx2 were conspicuously absent, except for sporadic instances of the eaeA gene in street-vended products. These findings uncovered a nuanced landscape of bacterial presence, with E. coli exhibiting a significant prevalence disparity among product sources, particularly with street-vended items showing markedly high contamination rates. It is advised that awareness programs should be established to reduce dairy product contamination among street vendors.
Keywords: Dairy; Street-vended; Escherichia coli; Contamination.

Key words: Keywords: Dairy; Street-vended; Escherichia coli; Contamination.