Bacillus cereus is the 2nd most frequent bacterial agent responsible for food-borne outbreaks in France and the 3rd in Europe. In addition, local and systemic infections have been reported, mainly describing individual cases or single hospital setting. The real incidence of such infection is unknown and information on genetic and phenotypic characteristics of the incriminated strains is generally scarce. We performed an extensive study of B. cereus strains isolated from patients and hospital environments from nine hospitals during a 5-year study, giving an overview of the consequences, sources and pathogenic patterns of B. cereus clinical infections. We demonstrated the occurrence of several hospital-cross-contaminations. Identical B. cereus strains were recovered from different patients and hospital environments for up to 2 years. We also clearly revealed the occurrence of inter hospital contaminations by the same strain. These cases represent the first documented events of nosocomial epidemy by B. cereus responsible for intra and inter hospitals contaminations. Indeed, contamination of different patients with the same strain of B. cereus was so far never shown. In addition, we propose a scheme for the characterization of B. cereus based on biochemical properties and genetic identification and highlight that main genetic signatures may carry a high pathogenic potential. Moreover, the characterization of antibiotic resistance shows an acquired resistance phenotype for rifampicin. This may provide indication to adjust the antibiotic treatment and care of patients.

The incidence-density rate of carbapenemase-producing isolates per 1000 hospital-days was low and 30-fold lower than that of carbapenem-NS isolates (0.125) and almost 300-fold lower than that of ESBL-producing isolates (1.104) in these French hospitals.

We studied the clinical isolates Enterococcus faecium NEF1, resistant to high levels of vancomycin (MIC, 512 g/ml) and teicoplanin (MIC, 64 g/ml); Enterococcus faecium BM4653 and BM4656 and Enterococcus avium BM4655, resistant to moderate levels of vancomycin (MIC, 32 g/ml) and to low levels of teicoplanin (MIC, 4 g/ml); and Enterococcus faecalis BM4654, moderately resistant to vancomycin (MIC, 16 g/ml) but susceptible to teicoplanin (MIC, 0.5 g/ml). (6,7,10,13,16,31), two E. faecalis strains (13), one Enterococcus gallinarum strain (8), and one Enterococcus raffinosus strain (37). Recently, the vanD operon was detected in a Ruminococcus sp., an anaerobic gram-positive bacterium from human bowel flora, suggesting a potential reservoir for vancomycin resistance genes in commensals of the digestive tract (17).VanD-type strains share various characteristics that distinguish them from VanA-and VanB-type enterococci. In particular, resistance to moderate levels of the two glycopeptides is constitutively expressed and is not transferable by conjugation to other enterococci (10,13,16,31). The organization of the vanD gene cluster, located exclusively in the chromosome, is similar to those of vanA and vanB (13,16

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Rouxiella chamberiensis gen. nov., sp. nov., a member of the family Enterobacteriaceae isolated from parenteral nutrition bags