Salmonella enterica serovar Infantis (Salmonella Infantis) is consistently isolated from broiler chickens, pigs, and humans worldwide. This study investigated 93 epidemiologically unrelated Salmonella Infantis strains isolated in Germany between 2005 and 2008 in respect to their transmission along the food chain. Various phenotypic and genotypic methods were applied, and the pathogenicity and resistance gene repertoire was determined. Phenotypically, 66% of the strains were susceptible to all 17 antimicrobials tested, while the others were almost all multidrug-resistant (two or more antimicrobial resistances), with different resistance profiles and preferentially isolated from broiler chickens. A number of phage types (PTs) were shared by strains from pigs, broiler chickens, and humans (predominated by PT 29). One, PT 1, was only detected in strains from pigs/pork and humans. Pulsed-field gel electrophoresis (PFGE) subdivided strains in seven different clusters, named A-G, consisting of 35 various XbaI profiles with coefficient of similarity values of 0.73-0.97. The majority of XbaI profiles were assigned to clusters A and C, and two predominant XbaI profiles were common in strains isolated from all sources investigated. Multi-locus sequence typing (MLST) analysis of selected strains representing the seven PFGE clusters revealed that they all belonged to ST32. The pathogenicity gene repertoire of 37 representative Salmonella Infantis strains analyzed by microarray was also identical. The resistance gene repertoire correlated perfectly with the phenotypic antimicrobial resistance profiles, and multidrug-resistant strains were associated with class 1 integrons. Overall, this study showed that two major closely related genotypes of Salmonella Infantis can transmit in Germany to humans through contaminated broiler meat or pork, and consequently presents a hazard for human health.

Aims: This study was performed in a well-established in vitro model to investigate whether the application of a glyphosate-containing herbicide might affect the bacterial communities and some biochemical parameters in a cow's rumen. Methods and Results: The test item was applied in two concentrations (high and low) for 5 days. In a second trial, fermentation vessels were inoculated with Clostridium sporogenes before the high dose was applied. Effluents were analysed by biochemical, microbiological and genetic methods. A marginal increase in short-chain fatty acid production and a reduction in NH 3 -N were observed. There were minor and rather equivocal changes in the composition of ruminal bacteria but no indications of a shift towards a more frequent abundance of pathogenic Clostridia species. Clostridium sporogenes counts declined consistently. Conclusions: No adverse effects of the herbicide on ruminal metabolism or composition of the bacterial communities could be detected. In particular, there was no evidence of a suspected stimulation of Clostridia growth. Significance and Impact of the Study: Antibiotic activity of glyphosate resulting in microbial imbalances has been postulated. In this exploratory study, however, intraruminal application of concentrations reflecting potential exposure of dairy cows or beef cattle did not exhibit significant effects on bacterial communities in a complex in vitro system. The low number of replicates (n = 3/dose) may leave some uncertainty.

Recent studies demonstrated the crucial role of c-Rel in directing Treg lineage commitment and its involvement in T helper 1 (Th1) cell-mediated autoimmune inflammation. We thus wondered whether these opposite functions of c-Rel influence the course of antiparasitic immune responses against Leishmania major, an accepted model for the impact of T-cell subsets on disease outcome. Here we show that c-Rel-deficient (rel(-/-) ) mice infected with L. major displayed dramatically exacerbated leishmaniasis and enhanced parasite burdens. In contrast to WT mice, IFN-γ and IL-17 production in response to L. major antigens was severely impaired in rel(-/-) mice. Reconstitution of Rag1(-/-) T-cell deficient mice with rel(-/-) CD4(+) T cells followed by L. major infection demonstrated that c-Rel-deficient T cells mount normal Th1 responses and are able to contain the infection. Similarly, Th1 differentiation of naïve CD4(+) cells in vitro was normal. Notably, a selective defect in IL-12 and IL-23 production was observed in rel(-/-) DCs compared with their WT counterparts. In conclusion, our data suggest that the expression of c-Rel in myeloid cells is essential for clearance of L. major and that this c-Rel-mediated effect is dominant over the lack of Tregs.

In this study, the population structure, incidence, and potential sources of human infection caused by the D-tartrate-fermenting variant of Salmonella enterica serovar Paratyphi B [S. Paratyphi B (DT؉)] was investigated. In Germany, the serovar is frequently isolated from broilers. Therefore, a selection of 108 epidemiologically unrelated S. enterica serovar Paratyphi B (DT؉) strains isolated in Germany between 2002 and 2010 especially from humans, poultry/poultry meat, and reptiles was investigated by phenotypic and genotypic methods. Strains isolated from poultry and products thereof were strongly associated with multilocus sequence type ST28 and showed antimicrobial multiresistance profiles. Pulsed-field gel electrophoresis XbaI profiles were highly homogeneous, with only a few minor XbaI profile variants. All strains isolated from reptiles, except one, were strongly associated with ST88, another distantly related type. Most of the strains were susceptible to antimicrobial agents, and XbaI profiles were heterogeneous. Strains isolated from humans yielded seven sequence types (STs) clustering in three distantly related lineages. The first lineage, comprising five STs, represented mainly strains belonging to ST43 and ST149. The other two lineages were represented only by one ST each, ST28 and ST88. The relatedness of strains based on the pathogenicity gene repertoire (102 markers tested) was mostly in agreement with the multilocus sequence type. Because ST28 was frequently isolated from poultry but rarely in humans over the 9-year period investigated, overall, this study indicates that in Germany S. enterica serovar Paratyphi B (DT؉) poses a health risk preferentially by contact with reptiles and, to a less extent, by exposure to poultry or poultry meat.