Microbiological contaminations of food constitute a very significant problem in the modern world. Despite the advanced techniques for detection of pathogenic microorganisms in food and the progress in treating diseases caused by them, the problem is still relevant. In the paper, there are described potential risks to people that are associated with the occurrence of verotoxic E.coli in food. Also, the paper presents a detailed profile of the serotype of E. coli O104:H4, which was a causative agent of the large outbreak of food poisoning in Germany in 2011. The occurrence of E.coli O104:H4 in humans, animals, and foods are discussed as is the occurrence of food-borne outbreaks caused by this group of microorganisms.