Safe ready to eat vegetables from farm to fork: The plant as a key for risk assessment and prevention of EHEC infections (acronym: Safe Salad)

Shigatoxin producing E. coli, causing EHEC infections, was the causal agent for major outbreaks in Sweden and abroad with leafy vegetables and sprouts. This pathogen is particularly severe due to its severe symptoms and low infectious dosis. The major source for contamination is associated with animal or human feces. Contamination can occur in the entire farm-to-fork chain and failure during preharvest may not be counteracted by processing. This project “Safe Salad” applies a novel and unique approach, as it focuses on the vector, namely the plant and its microflora. It uses a comprehensive approach from farm to fork. Results on interactions between cropping and processing environment, the leaf microflora and the prevalence of EHEC are used as a basis for risk assessment and identification of risk factors before harvest and of vegetables at risk. The impact of nitrogen upply to the crop is highlighted. Explanatory models for adhesion on the leaf via the existing biofilm and the significance of the leaf microbiota for disease development is studied in animal trials. Obtained results are implemented in intervention studies.