The article focuses on a study related to verocytotoxin-Producing escherichia coli (VTEC) serotype O26. Researchers have reported that the most important O serogroups associated with human disease are O26, O55, O91, O103, O111, O128 and O145. These strains cause a spectrum of disease that includes mild diarrhoea, haemorrhagic colitis, haemolytic uraemic syndrome and thrombocytopaenic purpura. Non-O157 VTEC strains are heterogeneous in their properties, and few laboratories screen for them in stools.