Presence of pathogenic E. coli in ready-to-be-eaten salad food from vendors in the Kumasi Metropolis, Ghana

This study was carried out to assess the distribution of E. coli O157:H7 in salad foods from restaurants and street food vendors within the Kumasi Metropolis from January to April, 2013. A detailed and well-structured questionnaire was first administered to 500 vendors with emphasis on knowledge of personal hygiene and salad food preparation. A total of 270 salad foods were aseptically sampled from vendors and transported on ice to the laboratory to determine the presence of total coliforms and E. coli (E. coli O157:H7) using standard microbiological methods. Out of the total samples analysed, all the samples were found to contain some counts of total coliforms and E. coli. Mean logcfu/g of total coliforms and E. coli were found to be 6.35 ± 0.09 and 5.1 ± 0.1, respectively. Three (3) samples showed positive to E. coli O157:H7 giving a prevalence of 1.1%. The low prevalence still suggests that E. coli O157:H7 is still a public health concern especially ready to be eaten salad foods since a relatively low infectious dose could be fatal. Although, street food vending has a positive impact on food supply and livelihoods of the ordinary people by providing cheap and affordable means of green-leafy or vegetable food in the Kumasi Metropolis, it poses a health risk which can result in serious health implications for consumers.