https://mediterraneanjournals.com/index.php/vmr <p><strong>Veterinary Medicine Reports</strong> is an international open-access peer-reviewed journal, based on a continuous publication model, and aims to publish original works of high quality, from MENA region countries, covering all veterinary medicine fields.</p> en-US Veterinary Medicine Reports https://mediterraneanjournals.com/index.php/vmr/article/view/603 <p>Shiga toxin-producing <em>Escherichia coli</em> (STEC) O157:H7 is the most prevalent serotype associated with severe diseases worldwide. Biofilms by STEC O157:H7 constitute a high risk to public health and the food industry since they allow cross-contamination of surfaces and the consequent transmission to humans. This study aimed to detect the presence of adhesins genotypically and determine the ability to form biofilm and the curli expression in a collection of 30 O157:H7 strains from healthy cattle and human cases. The <em>efa1</em>, <em>iha</em>, <em>fimCD</em>, <em>ehaA</em>, <em>lpfA1-3</em>, and <em>lpfA2-2 </em>genes were detected in all strains; <em>cah </em>was frequently detected in strains isolated from humans (16/20), and <em>agn43 </em>was the least prevalent gene (3/30). All strains could form a biofilm, although those isolated from cattle were the most biofilm-formers. The curli-negative phenotype was the most prevalent phenotype observed at 37 °C and room temperature. The association between curli production and biofilm formation could not be determined, but the highest proportion of curli-positive strains at room temperature were strong biofilm-formers. These results highlight the possibility of the persistence of STEC O157:H7 in environmental conditions and food processing facilities, increasing the risk of contamination or infection.</p> María Emilia Cáceres Silvina Lavayen Claudio Marcelo Zotta David Montero Roberto Vidal Analía Inés Etcheverría Nora Lía Padola Copyright (c) 2022 Cáceres ME et al https://creativecommons.org/licenses/by/4.0 2022-02-22 2022-02-22