This study aimed to evaluate the occurrence of Shiga toxin-producing Escherichia coli (STEC) in feces samples, water, feed, raw milk, pasteurized milk, Minas Frescal cheese, and ground beef. Seventy samples (40 of feces, 10 of raw milk, 5 of pasteurized milk, 5 of ground beef, 4 of Minas Frescal cheese, 4 of water, and 2 of feed) were collected in two farms of dairy cattle and two farms of beef cattle and in commercial establishments. The samples were processed according to standard methodologies using biochemical methods and molecular and biological assays. Among 209 identified bacterial isolates as E. coli, 120, 70, 7, 7, 3, 2, and zero were obtained from samples of feces, water, feed, ground beef, pasteurized milk, Minas Frescal cheese, and raw milk, respectively. An isolate from water sample coming from a beef cattle farm was identified as E. coli STEC. This isolate showed cytotoxic effect in Vero cells and the EhlyA gene encoding entero-hemolysin. Therefore it is justified to develop studies to limit the spread of this pathogen.21624812486Aidar-ugrinovich, L., Blanco, J., Blanco, M., Blanco, J.E., Leomil, L., Dhabi, G., Mora A.Onuma, D.L., Pestana de Castro, A.F., Serotypes, virulence genes, and intimin types of Shiga toxin-producing Escherichia coli (STEC) and enteropathogenic E. coli (EPEC) isolated from calves in São Paulo, Brazil (2007) International Journal of Food Microbiology, 115, pp. 297-306Bentancor, A., Vilte, D.A., Rumi, M.V., Carbonari, C.C., Chinen, I., Larzábal, M., Cataldi, A., Mercado, E.C., Characterization of non-Shiga toxin-producing Escherichia coli O157 strains isolated from dogs (2010) Revista Argentina de Microbiología, 42, pp. 46-48Bergamini, A.M., Simões, M., Irino, K., Gomes, T.A.T., Guth, B.E.C., Prevalence and characteristics of Shiga toxin-producing Escherichia coli (STEC) strains in ground beef in São Paulo, Brazil (2007) Brazilian Journal of Microbiology, 38, pp. 553-556Bettelheim, K.A., Kuzevski, A., Gilbert, R.A., Krause, D.O., McSweeney, C.S., The diversity of Escherichia coli serotypes and biotypes in cattle faeces (2005) Journal of Applied Microbiology, 98, pp. 699-709Bosilevac, J.M., Koohmaraie, M., Prevalence and Characterization of Non-O157 Shiga Toxin-Producing Escherichia coli Isolates from Commercial Ground Beef in the United States (2011) Applied and Environmental Microbiology, 77 (6), pp. 2103-2112Caprioli, A., Morabito, S., Brugère, H., Oswald, E., Enterohaemorrhagic Escherichia coli: emerging issues on virulence and modes of transmission (2005) Veterinary Research, 36, pp. 289-311Cergolle-Novella, M.C., Nishimura, L.S., Santos, L.F., Irino, K., Vaz, T.M.I., Pestana de Castro, A.F., Leomil, L., Guth, B.E.C., Stx genotypes and antimicrobial resistance profiles of Shiga toxin-producing Escherichia coli strains isolated from human infections, cattle and foods in Brazil (2006) FEMS Microbiology Letters, 259, pp. 234-239Cergolle-Novella, M.C., Nishimura, L.S., Santos, L.F., Irino, K., Vaz, T.M.I., Bergamini, A.M., Guth, B.E.C., Distribution of virulence profiles related to new toxins and putative adhesins in Shiga toxin-producing Escherichia coli isolated from diverse sources in Brazil (2007) FEMS Microbiology Letters, 274, pp. 329-334Cerqueira, A.M.F., Guth, B.E.C., Joaquim, R.M., Andrade, J.R.C., High occurence of Shiga toxin-producing Escherichia coli (STEC) in healthy cattle in Rio de Janeiro State, Brazil (1999) Veterinary Microbiology, 70, pp. 111-121Cho, S., Diez-Gonzales, F., Fossler, C.P., Wells, S.J., Hedberg, C.W., Kaneene, J.B., Ruegg, P.L., Bender, J.B., Prevalence of Shiga toxin-encoding bacteria and Shiga toxin-producing Escherichia coli isolates from dairy farms and county fair (2006) Veterinary Microbiology, 118, pp. 289-298Donnenberg, M.S., Whittam, T.S., Pathogenesis and evolution of virulence in enteropathogenic and enterohemorrhagic Escherichia coli (2001) Journal of Clinical Investigation, 107, pp. 539-548Dumke, R., Schroter-Bobsin, U., Jacobs, E., Roske, I., Detection of phages carrying the Shiga toxin 1 and 2 genes in waste water and river water samples (2006) Letters in Applied Microbiology, 42, pp. 48-53Farah, S.M.S.S., Souza, E.M., Pedrosa, F.O., Irino, K., Silva, L.R., Rigo, L.U., Steffens, M.B.R., Fadel-Pichet, C.M.T., Phenotypic and genotypic traits of Shiga toxin-producing Escherichia coli strains isolated from beef cattle from Parana State, southern Brazil (2007) Letters in Applied Microbiology, 44, pp. 606-612Gentry, M.K., Dalrymple, J.M., Quantitative micro titer cytotoxicity assay for Shigella toxin (1980) Journal of Clinical Microbiology, 12 (3), pp. 361-366Guth, B.E.C., Gomes, T.A.T., Vaz, T.M.I., Irino, K., Inability to decarboxylate lysine as a presumptive marker to identify Shiga toxin-producing Escherichia coli strains of serogroup O111 (2003) Journal of Clinical Microbiology, 41, p. 3450Irino, K., Kato, M.A., Vaz, T.M., Ramos, I.I., Souza, M.A., Cruz, A.S., Gomes, T.A., Guth, B.E.C., Serotypes and virulence markers of Shiga toxin-producing Escherichia coli (STEC) isolated from dairy cattle in São Paulo state, Brazil (2005) Veterinary Microbiology, 105 (1), pp. 29-36Jenkins, C., Perry, N.T., Cheasty, T., Shaw, D.J., Frankel, G., Dougan, G., Gunn, G.J., Paton, J.C., Distribution of the saa gene in strains of Shiga toxin-producing Escherichia coli of human and bovine origins (2003) Journal of Clinical Microbiology, 41, pp. 1775-1778Jure, M.A., Condorí, S., Leotta, G.A., Chinen, I., Miliwebsky, E., Allori, C., Aulet, O., De Castillo, M.C., Detección, aislamiento y caracterización de Escherichia coli productor de toxina Shiga a partir de carne molida fresca proveniente de carnicerías de Concepción, provincia de Tucumán (2010) Revista Argentina de Microbiología, 42 (4), pp. 284-287Kaper, J.B., Nataro, J.P., Mobley, H.L.T., Pathogenic Escherichia coli (2004) Nature Reviews, 2, pp. 123-140Karmali, M.A., Use de comparative genomics as a tool to assess the clinical and public health significance of emerging Shiga toxin-producing Escherichia coli serotypes (2005) Meat Science, 71, pp. 62-71Keskimaki, M., Eklund, M., Pesonen, H., Heiskanen, T., Siitonen, A., The Study Group. EPEC, EAEC and STEC in stool specimens: prevalence and molecular epidemiology of isolates (2001) Diagnostic of Microbiology Infectious Disease, 40, pp. 151-156Kornacki, J.L., Johnson, J.L., Enterobacteriaceae, coliforms, and Escherichia coli as quality and safety indicators (2001) Compendium of methods for the microbiological examination of foods, pp. 69-82. , Downes, F.P. and Ito, K. (eds). American Public Health Association (APHA), Washington, D. CKuhnert, P., Boerlin, P., Frey, J., Target genes for virulence assessment of Escherichia coli isolates from water, food and environment (2000) FEMS Microbiology Reviews, 24, pp. 107-117Leomil, L., Aidar-Ugrinovich, L., Guth, B.E.C., Irino, K., Vettorato, M.P., Onuma, D.L., Pestana de Castro, A.F., Frequency of Shiga toxin producing Escherichia coli (STEC) isolates among diarrheic and non-diarrheic calves in Brazil (2003) Veterinary Microbiology, 97 (2), pp. 103-109Madic, J., Vingadassalon, N., De Garam, C.P., Marault, M., Scheutz, F., Brugère, H., Jamet, E., Auvray, F., Detection of Shiga toxin-producing Escherichia coli serotypes O26:H11, O103:H2, O111:H8, O145:H28, and O157:H7 in raw-milk cheeses by using multiplex real-time PCR (2011) Applied and Environmental Microbiology, 77 (6), pp. 2035-2041Maldonado, Y., Fiser, J.F., Nakatsu, C.H., Bhunia, A.K., Cytotoxicity potential and genotypic characterization of Escherichia coli isolates from environmental and food sources (2005) Applied and Environmental Microbiology, 71, pp. 1890-1898Meng, J., Doyle, M.P., Microbiology of Shiga toxin-producing Escherichia coli in foods (1998) Escherichia coli O157:H7 and other Shiga toxin-producing E. coli strains, pp. 92-108. , Kaper, J.B. e O'Brien, A.D. (Ed). Washington, DC: ASM PressMonday, S.R., Beisaw, A., Feng, P.C.H., Identification of Shiga toxigenic Escherichia coli seropathotypes A and B by multiplex PCR (2007) Molecular and Cellular Probes, 21, pp. 308-311Moreira, C.N., Pereira, M.A., Brod, C.S., Rodriguez, D.P., Carvalhal, J.B., Aleixo, J.A.G., Shiga toxin-producing Escherichia coli (STEC) isolated from healthy dairy cattle in southern Brazil (2003) Veterinary Microbiology, 93, pp. 179-183Nataro, J.P., Kaper, J.B., Diarrheagenic Escherichia coli (1998) Clinical Microbiology Reviews, 11 (1), pp. 142-201O'Loughlin, E.V., Robin-Browne, R.M., Effect of Shiga toxin and Shiga-like Toxin on eukaryotic cells (2001) Microbes and Infection, 3, pp. 493-507Oliveira, M.G., Brito, J.R.F., Gomes, T.A.T., Guth, B.E.C., Vieira, M.A.M., Naves, Z.V.F., Vaz, T.M.I., Irino, K., Diversity of virulence profiles of Shiga toxin-producing Escherichia coli serotypes in food-producing animals in Brazil (2008) International Journal of Food Microbiology, 127, pp. 139-146Osek, J., Development of a multiplex PCR approach for the identification of Shiga toxin-producing Escherichia coli strains and their major virulence factor genes (2003) Journal of Applied Microbiology, 95, pp. 1217-1225Paton, J.C., Paton, A.W., Pathogenesis and diagnosis of Shiga toxin-producing Escherichia coli infections (1998) Clinical Microbiology Reviews, 11 (3), pp. 450-470Shelton, D.R., Karns, J.S., Higgins, J.A., Van Kessel, J.A.S., Perdue, M., Belt, K.T., Russell-Anelli, J., Debroy, C., Impact of microbial diversity on rapid detection of enterohemorrhagic Escherichia coli in surface waters (2006) FEMS Microbiology Letters, 261, pp. 95-101Silva, Z.N., Cunha, A.S., Lins, M.C., Carneiro, L.A., Almeida, A.C.F., Queiroz, M.L.P., Isolation and serological identification of enteropathogenic Escherichia coli in pasteurized milk in Brazil (2001) Revista da Saúde Pública, 35 (4), pp. 375-379Song, T., Toma, C., Nakasone, N., Iwanaga, M., Sensitive and rapid detection of Shigella and enteroinvasive Escherichia coli by a loop-mediated isothermal amplification method (2005) FEMS Microbiology Letters, 243, pp. 259-263Souza, R.L., Nishimura, L.S., Guth, B.E.C., Uncommon Shiga toxin-producing Escherichia coli serotype O165: HNM as cause of hemolytic uremic syndrome in São Paulo, Brazil (2007) Diagnostic Microbiology and Infectious Disease, 59, pp. 223-225Stevens, M.P., Van Diemen, P.M., Dziva, F., Jones, P.W., Wallis, T.S., Options for the control of enterohaemorrhagic Escherichia coli in ruminants (2002) Microbiology, 148, pp. 3767-3778Timm, C.D., Irino, K., Gomes, T.A.T., Vieira, M.A., Guth, B.E.C., Vaz, T.M.I., Moreira, C.N., Aleixo, J.A.G., Virulence markers and serotypes of Shiga toxin-producing Escherichia coli isolated from cattle in Rio Grande do Sul, Brazil (2007) Letters in applied microbiology, 44, pp. 419-425Tschäpe, H., Fruth, A., Enterohemorrhagic Escherichia coli (2001) Emerging bacterial pathogens. Contributions to Microbiology, pp. 1-11. , Müldorfer, I.Schäfer, K.P. (eds) Basel. KargerVaz, T.M.I., Irino, K., Nishimura, L.S., Cergole-Novella, M.C., Guth, B.E.C., Genetic heterogeneity of Shiga toxin-producing Escherichia coli strains isolated in São Paulo, Brazil, from 1976-through 2003, as revealed by pulsed field gel electrophoresis (2006) Journal of Clinical Microbiology, 44, pp. 798-804Vettorato, M.P., Leomil, L., Guth, B.E.C., Irino, K., Pestana de Castro, A.F., Properties of Shiga toxin-producing Escherichia coli (STEC) isolates from sheep in the state of São Paulo, Brazil (2003) Veterinary Microbiology, 95 (1), pp. 103-109Vidal, M., Kruger, E., Durán, C., Lagos, R., Levine, M., Prado, V., Toro, C., Vidal, R., Single multiplex PCR assay to identify simultaneously the six categories of diarrheagenic Escherichia coli associated with enteric infections (2005) Journal of Clinical Microbiology, 43 (10), pp. 5362-5365Yoon, J.W., Hovde, C.J., All blood, no stool: enterohemorrhagic Escherichia coli O157:H7 infection (2008) Journal of Veterinary Science, 9, pp. 219-231Wang, G., Zhao, T., Doyle, M.P., Fate of enterohemorrhagic Escherichia coli O157:H7 in bovine feces (1996) Applied and Environmental Microbiology, 62 (7), pp. 2567-2570(2011) EHEC outbreak: Update 15, , http://www.euro.who.int/en/what-we-do/health-topics/emergencies/international-health-regulations/news/news/2011/06/ehec-outbreak-update-15, on 15/07/2013