Abstract:
Escherichia coli is a genetically distinct group of bacteria whose members are not normally pathogens found in the normal microbiome of humans and animals' digestive tracts. Diarrhoea, Haemorrhagic Colitis (HC), Haemolytic Uremic Syndrome (HUS), Urinary Tract Infections (UTIs), Sepsis, and Neonatal Meningitis are forms of bacterial strains that have acquired virulence properties that help them to cause tremendous intestinal and extra-intestinal disorders. E. coli has been reported to cause disease outbreaks related to the consumption of fresh fruits and vegetables such as (lettuce, cucumber, carrot, cabbage, pineapple, watermelon and papaya.). These fresh produces are contaminated with E. coli during field cultivation or during application of organic manure or during harvest, transport, processing, storage and distribution. In Nigeria, there have been reports of outbreaks involving E. coli from fresh produce to date. Fresh fruits and vegetables have been collected around Lagos and Ogun states local street markets to isolate E. coli. A total of 64 samples were tested for presence of E. coli using Sorbitol MacConkey Agar and MacConkey Agar plates. All sampled had presumptive STEC, molecular identification of selected isolates (n = 21) randomly for STEC virulence genes (stx1 stx2 and eae) using multiplex PCR was done. The total viable count (TVC) for presumptive STEC in the samples was in the range of 4.5-7.8 log10cfu/g. Lettuce from Ibafo had the highest total viable count of 7.8Log10CFU/g. Virulence gene (stx1) was detected only in watermelon from Magboro using Multiplex PCR. From this result, the presence of STEC poses a threat to public health which could lead to foodborne illnesses including haemorrhagic colitis (HC) or haemolytic uremic syndrome (HUS). Findings on this study call for immediate actions by the Nigerian Food Safety Agency to ensure food safety regulations in the fresh produce supply chain in the local markets nationwide. In conclusion isolating E. coli from fresh-cut produce by using selective enrichment broth and selective media and molecular characterizations of the isolates. One isolate was found to carry stx1 gene, which is responsible for haemolytic colitis and haemorrhagic uremic syndrome, based on the risk of the presence of STEC from fresh produce.
