[Characterization of Escherichia coli strains isolated from man and seafood]

The collection of 100 Escherichia coli strains isolated in clinical samples (30), healthy carriers (30) and seafood (40), was characterized by conventional tests on API 20 E gallery and on specific reactive media. These strains were examined by full biotyping with 10 tests, serotyped using 12 monovalent sera and tested with 11 antibiotics. Six persons harboured higher percentages of resistant E. coli strains than seafood. Primary and secondary biotypes based on the use of four primary tests and six secondary tests were prospected. The most frequently encountered primary biotypes were: biotype 1 (42%), 11 (16%) and 9 (12%). These biotypes belonged to 32 secondary biotypes and 43 complete biotypes. The pathogenic serotypes isolated during this survey were O126B16 (3%), O26B6 (2%), O119B14 (2%), O86B7 (2%), O111B4 (2%), O55B5 (1%), O114K90 (1%) and O128B12 (1%). Two strains of E. coli were enteroinvasive by the test of Sérény. Results suggested that these typing methods may be used for discriminating strains of E. coli.