Caracterização fenotípica pelo antibiograma de cepas de Escherichia coli isoladas de manipuladores, de leite cru e de queijo "Minas Frescal" em um laticínio de Goiás, Brasil

The present work aimed to type E. coli strains obtained from handlers hands and noses, raw milk and Minas Frescal cheese produced by a dairy milk processing plant in Goias, Brazil in order to establish a contamination relationship between the sources of E. coli and cheese. Twenty-four samples were collected from raw milk and Minas Frescal cheese, 46 from hands and 46 from noses of handlers involved in the cheese manufacturing, between March/2004 and February/2005. All 69 E. coli strains isolated were submitted to the susceptibility test for six antimicrobials (ampicillin, cephalothin, ciprofloxacin, gentamicin, trimethopim-sulphamethoxazole and tetracycline. The strains were grouped in 17 different phenotypic susceptibility profiles (A-Q). The test allowed to establish correlation among a cheese strain (14Qb) and a handler (10M1) strain that presented the same susceptibility profile (E) suggesting a possible product contamination during the handling. In conclusion, the phenotypic susceptibility profiles determinated by the antibiogram method failed to establish a correlation between the strains obtained from the probable sources (handlers and milk) and the final products.