Fatores de virulência, sorotipos e susceptibilidade antimicrobiana de amostras de Escherichia coli isoladas de alimentos no estado de Minas Gerais, Brasil

Abstract

Occurrence of foodborne diseases, relevant public health problem, has increased significantly not only in Brazil but also in several countries. In order to ensure food quality and safety, many institutional initiatives, legal and community, have been developed in our country. Among these, we highlight the Food Quality Monitoring Program (called PROGVISA-MG), an important instrument for planning and structuring actions of Health Surveillance in Minas Gerais state and, in addition, compliance with national and state guidelines in as regarding the prevention and investigation of foodborne disease outbreaks. Among the main microbial foods contaminants highlight to Escherichia coli, bacterium that is part of the humans intestinal tract and warm-blooded animals, being constantly eliminated in the environment, polluting the soil, water and food. These bacteria, beises being used as a health indicator, may also cause foodborne diseases, since there are many strains of diarrheagenic E. coli to humans and animals. In this context, we aimed to identify the presence of E. coli in food collected by Food Quality Monitoring Program and foodborne diseases outbreaks in Minas Gerais state, and evalute them for antimicrobial susceptibility, the presence of virulence factors (eae, bfpA, eltB, estA, st1, stx1, stx2, ipaH e aatA) and serotypes of diarrheagenic E. coli. In 51 (12.9%) of 396 foods analyzed, was detected the presence of the coliform group 45ºC and 41 (10.3%) of the presence of E. coli, mainly among dairy products and meals ready to consumption. By analysis of 220 strains on the antimicrobial susceptibility profile, it was observed that 60 (27.3%) showed resistance or intermediate resistance profile of at least one antimicrobial agent. The drugs of the class of aminoglycosides (amikacin and gentamicin) were more effective, those of the -lactam class, especially ampicillin, showed the highest percentage of resistant strains, 10.9%. The resistance to more than one antimicrobial agent and more than one therapeutic group was observed in 25 (41,7%) 8 (13,3%) strains, respectively. The multidrug resistance, measured by index MAR (Multiple Antibiotic Restistence) was observed in 6 (10%) sample. Only one strain was producing EBSL (extended spectrum -lactamase). For virulence factors, it was not identified characteristic genes of EPEC, STEC, EAEC and EIEC pathotypes. The presence of ETEC characteristic pathotype was limited to two strains (0.9%), isolated from a meal made by chicken (from a foodborne diseases outbreaks) and the other a cheese bread (from the the Food Quality Monitoring Program), both containing the genes eltB, estA, st1, responsible for the production of enterotoxin LT, STp and STh, respectively, and characterized as serotypes O9: H10 and O9: H33, not seen in E. coli isolated from food samples yet.