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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. -® Copyright 2012, Mary Ann Liebert, Inc. 2012

This study was supported by the Health Protection Agency, the Federal Institute for Risk Assessment (BfR-46-001; 45-005), and the Fondo de Investigación Sanitaria of the Instituto de Salud Carlos III of Spain (project FIS PI11/00808, cofunded by the European Regional Development Fund of the European Union: a Way of Making Europe). I.R. received a postdoctoral grant from Fundación Ramón Areces, Madrid, Spain.

The cattle are considered hosts of the Hardjo serovar, causing economic damages due to the reproductive failures like abortions and infertility. The serovar Hardjo usually remains in the reproductive tract and also in the renal tubules where it is eliminated intermittently in the urine for months. Placental remnants, the aborted fetus and contaminated urine promote the permanence of this bacterium within the herd for years. Thus, the objective of this study was to monitor for prolonged period, cows naturally infected with Leptospira ssp. through microbiological culture, serological examination and DNA detection of the pathogen in the urine. The dairy herd was composed of 50 breeding cows with a history of abortion and infertility, without leptospirosis vaccine and located in the northern region of Paraná. Blood and urine samples were collected and laboratorial diagnosis were performed five times at intervals of four months. Blood samples were collected from the all 50 animals and the serum was submitted to the microscopic agglutination test (MAT) for the detection of anti-leptospira antibodies. Of the total cows, 20 showed antibody titres ? 1: 100 in MAT and urine samples were collected from only those animals with higher titers to perform nested-PCR (n-PCR) and bacterial isolation per culture. In addition, two urine samples from five animals with antibody titers < 1: 100 were collected in MAT for n-PCR. Serovar Hardjo was considered the most frequent during the serological monitoring of the animals evaluated. The n-PCR technique was able to detect leptospiral DNA in the urine of animals with MAT ? 1: 100 antibody titers and urine from animals whose titers were < 1: 100. Sequencing of the leptospiral amplicons shared 100% nucleotide sequence identity with the Leptospira interrogans species. Positive n-PCR results from animals with titers of < 1: 100 suggest that the cut-off of MAT is could be not sufficient to detect renal carriers, so it is also important to use n-PCR as an additional diagnostic tool for identify infected animals with Hardjo serovar and whose serology was negative.

Seventy-nine Salmonella enterica serovar 1,4,[5],12:i:- isolates from patients admitted at the Government Hospital of the Ministry of Public Health were tested for their minimum inhibitory concentration using micro dilution plate test. All isolates were sensitive to ciprofloxacin. The isolates were resistant to ampicillin (75.95%), cefoperazone (74.68%), chloramphenical (41.77%), gentamicin (63.29%), nalidixic acid (54.43%) and trimethoprim-sulfamethoxazole (81.01%). The highest proportion of antimicrobial resistance profiles among the isolates was AMP-CFP-GEN-NAL-SXT (15.2%). Only 3 isolates (3.8%) produced extendedspectrum beta-lactamase enzyme that cause resistance to cepharosporins.

We describe a one‐dimensional probabilistic model of the role of domestic food handling behaviors on salmonellosis risk associated with the consumption of eggs and egg‐containing foods. Six categories of egg‐containing foods were defined based on the amount of egg contained in the food, whether eggs are pooled, and the degree of cooking practiced by consumers. We used bootstrap simulation to quantify uncertainty in risk estimates due to sampling error, and sensitivity analysis to identify key sources of variability and uncertainty in the model. Because of typical model characteristics such as nonlinearity, interaction between inputs, thresholds, and saturation points, Sobol's method, a novel sensitivity analysis approach, was used to identify key sources of variability. Based on the mean probability of illness, examples of foods from the food categories ranked from most to least risk of illness were: (1) home‐made salad dressings/ice cream; (2) fried eggs/boiled eggs; (3) omelettes; and (4) baked foods/breads. For food categories that may include uncooked eggs (e.g., home‐made salad dressings/ice cream), consumer handling conditions such as storage time and temperature after food preparation were the key sources of variability. In contrast, for food categories associated with undercooked eggs (e.g., fried/soft‐boiled eggs), the initial level of Salmonella contamination and the log10 reduction due to cooking were the key sources of variability. Important sources of uncertainty varied with both the risk percentile and the food category under consideration. This work adds to previous risk assessments focused on egg production and storage practices, and provides a science‐based approach to inform consumer risk communications regarding safe egg handling practices.

The Wellcome Trust Sanger Institute authors were funded by Wellcome Trust Award #098051. V.K.W. was supported by the Wellcome Trust (#098051) and the National Institute of Health Research (NIHR) Cambridge Biomedical Research Centre (BRC). N.F. was supported by the Wellcome Trust Research Fellowship #WT092152MA. N.F., R.S.H. and this work were supported by a strategic award from the Wellcome Trust for the MLW Clinical Research Programme (#101113/Z/13/Z). C.P. was funded by The Wellcome Trust Mahidol University Oxford Tropical Medicine Research Programme, supported by the Wellcome Trust of Great Britain (Major Overseas Programmes—Thailand Unit Core Grant), the European Society for Paediatric Infectious Diseases and University of Oxford-Li Ka Shing Global Health Foundation. D.D., P.N. and V.D. were supported by the Wellcome Trust (core grant #089275/H/09/Z). Z.A.D. was supported by the Wellcome Trust (Strategic award #106158). K.E.H. was supported by the NHMRC of Australia (fellowship #1061409) and the Victorian Life Sciences Computation Initiative (VLSCI; grant #VR0082). C.A.M. was supported by a Clinical Research Fellowship from GlaxoSmithKline and PJH by a UK Medical Research Council PhD studentship. This work forms part of an EU FP7 Marie Curie Actions Industry Academia Partnerships and Pathways (IAPP) Consortium Programme, entitled GENDRIVAX (Genome-driven vaccine development for bacterial infections), involving the Wellcome Trust Sanger Institute, KEMRI Nairobi and Novartis Vaccines Institute for Global Health. The Institut Pasteur (IP) authors were funded by the IP, the Institut de Veille Sanitaire and by the French Government 'Investissement d'Avenir' programme (Integrative Biology of Emerging Infectious Diseases Laboratory of Excellence, grant #ANR-10-LABX-62-IBEID). C.H.W. was supported by the UK Medical Research Council (MRC; #MR/J003999/1). C.O. was supported by Society in Science, The Branco Weiss Fellowship, administered by the ETH Zurich. A.K.C. was supported by the MRC (#G1100100/1). J.J. was supported by the antibiotic resistance surveillance project in DR Congo, funded by Project 2.01 of the Third Framework Agreement between the Belgian Directorate General of Development Cooperation and the Institute of Tropical Medicine, Antwerp, Belgium. F.M. was supported by a research grant from the Bill and Melinda Gates Foundation. J.A.C. was supported by the joint US National Institutes of Health-National Science Foundation Ecology and Evolution of Infectious Disease program (#R01 TW009237) and the UK Biotechnology and Biological Sciences Research Council (BBSRC; #BB/J010367/1), and by UK BBSRC Zoonoses in Emerging Livestock Systems awards #BB/L017679, #BB/L018926 and #BB/L018845. S.K. was supported by the NIH Grant Number R01 AI099525-02. S.B. is a Sir Henry Dale Fellow, jointly funded by the Wellcome Trust and the Royal Society (#100087/Z/12/Z). S.O. was supported by the National Institute Of Allergy And Infectious Diseases of the National Institutes of Health (#R01AI097493). C.D. was supported by the University of Oxford-Li Ka Shing Global Health Programme. A.E.M. was supported by a Biotechnology and Biological Sciences Research Council award (#BB/M014088/1). P.T. was supported by the Wellcome Trust of Great Britain (Major Overseas Programmes—Thailand Unit Core Grant) and University of Oxford-Li Ka Shing Global Health Foundation.

The objective of the study was to investigate the antimicrobial activity of tunta on Salmonella enterica subspecies enterica serovar Typhimurium. A natural isolate of this bacterium was used that was resistant to chloramphenicol. The experiment required the preparation of a standard solution of 0,8 g / ml of tunta extract. The Kirby Bauer technique was used for the antimicrobial evaluation of the tests and the Duraffourd scale to measure the level of sensitivity. Resulting, for the ten technical repetitions of the experimental group, an average halo of 10,40 mm and a standard deviation of 0,63 of DHI (level of limit sensitivity, according to said scale). In conclusion, our work shows evidence that tunta has an antimicrobial effect at a borderline sensitivity level on Salmonella enterica subspecies enterica serovar Typhimurium. After more in-depth research, this derivative of Solanum Jueepczukii could become an alternative for the development of antibiotics of natural origin and allow a sustainable development of Andean cultures.

Introduction: Salmonella enterica serovar Typhimurium ST313 is an invasive and phylogenetically distinct lineage present in sub-Saharan Africa. We report the presence of S. Typhimurium ST313 from patients in the Democratic Republic of Congo and Nigeria. Methodology: Eighteen S. Typhimurium ST313 isolates were characterized by antimicrobial susceptibility testing, pulsed-field gel electrophoresis (PFGE), and multilocus sequence typing (MLST). Additionally, six of the isolates were characterized by whole genome sequence typing (WGST). The presence of a putative virulence determinant was examined in 177 Salmonella isolates belonging to 57 different serovars. Results: All S. Typhimurium ST313 isolates harbored resistant genes encoded by blaTEM1b, catA1, strA/B, sul1, and dfrA1. Additionally, aac(6')1aa gene was detected. Phylogenetic analyses revealed close genetic relationships among Congolese and Nigerian isolates from both blood and stool. Comparative genomic analyses identified a putative virulence fragment (ST313-TD) unique to S. Typhimurium ST313 and S. Dublin. Conclusion: We showed in a limited number of isolates that S. Typhimurium ST313 is a prevalent sequence-type causing gastrointestinal diseases and septicemia in patients from Nigeria and DRC. We found three distinct phylogenetic clusters based on the origin of isolation suggesting some spatial evolution. Comparative genomics showed an interesting putative virulence fragment (ST313-TD) unique to S. Typhimurium ST313 and invasive S. Dublin. © 2013 Leekitcharoenphon et al. ; SCOPUS: ar.j ; info:eu-repo/semantics/published

Poultry feed is a leading source of Salmonella infection in poultry. In Switzerland, heat-treated feed is used to reduce Salmonella incursions into flocks in conventional poultry production. By contrast, organic feed is only treated with organic acids. In 2019, the Swiss National Reference Center for Enteropathogenic Bacteria identified the rare serovar S. Jerusalem from samples of organic soya feed. Further, in July 2020, the European Union's Rapid Alert System for Food and Feed published a notification of the detection of S. Jerusalem in soya expeller from Italy. During 2020, seven S. Jerusalem isolates from seven different poultry productions distributed over six cantons in Switzerland were reported, providing further evidence of a possible outbreak. Using whole-genome sequencing (WGS), S. Jerusalem isolates from feed and from animals in Switzerland were further characterized and compared to S. Jerusalem from organic poultry farm environments in Italy. WGS results showed that feed isolates and isolates from Swiss and Italian poultry flocks belonged to the sequence type (ST)1028, grouped in a very tight cluster, and were closely related. This outbreak highlights the risk of spreading Salmonella by feed and emphasizes the need for a heat-treatment process for feed, also in organic poultry production.

Poultry feed is a leading source of Salmonella infection in poultry. In Switzerland, heat-treated feed is used to reduce Salmonella incursions into flocks in conventional poultry production. By contrast, organic feed is only treated with organic acids. In 2019, the Swiss National Reference Center for Enteropathogenic Bacteria identified the rare serovar S. Jerusalem from samples of organic soya feed. Further, in July 2020, the European Union's Rapid Alert System for Food and Feed published a notification of the detection of S. Jerusalem in soya expeller from Italy. During 2020, seven S. Jerusalem isolates from seven different poultry productions distributed over six cantons in Switzerland were reported, providing further evidence of a possible outbreak. Using whole-genome sequencing (WGS), S. Jerusalem isolates from feed and from animals in Switzerland were further characterized and compared to S. Jerusalem from organic poultry farm environments in Italy. WGS results showed that feed isolates and isolates from Swiss and Italian poultry flocks belonged to the sequence type (ST)1028, grouped in a very tight cluster, and were closely related. This outbreak highlights the risk of spreading Salmonella by feed and emphasizes the need for a heat-treatment process for feed, also in organic poultry production.

Salmonella enterica serovar Typhimurium DT 104 is the major pathogen for salmonellosis outbreaks in Europe. We tested if the probiotic bacterium Enterococcus faecium NCIMB 10415 can prevent or alleviate salmonellosis. Therefore, piglets of the German Landrace breed that were treated with E. faecium (n=16) as a feed additive and untreated controls (n=16) were challenged with S. Typhimurium 10 days after weaning. The presence of salmonellae in feces and selected organs, as well as the immune response, were investigated. Piglets treated with E. faecium gained less weight than control piglets (P=0.05). The feeding of E. faecium had no effect on the fecal shedding of salmonellae and resulted in a higher abundance of the pathogen in tonsils of all challenged animals. The specific (anti-Salmonella IgG) and nonspecific (haptoglobin) humoral immune responses as well as the cellular immune response (T helper cells, cytotoxic T cells, regulatory T cells, +¦+¦ T cells, and B cells) in the lymph nodes, Peyer's patches of different segments of the intestine (jejunal and ileocecal), the ileal papilla, and in the blood were affected in the course of time after infection (P < 0.05) but not by the E. faecium treatment. These results led to the conclusion that E. faecium may not have beneficial effects on the performance of weaned piglets in the case of S. Typhimurium infection. Therefore, we suggest a critical discussion and reconsideration of E. faecium NCIMB 10415 administration as a probiotic for pigs.

The epidemiology of typhoid fever in Lao People`s Democratic Republic is poorly defined. Estimating the burden of typhoid fever in endemic countries is complex due to the cost and limitations of population-based surveillance; serological approaches may be a more cost-effective alternative. ELISAs were performed on 937 serum samples (317 children and 620 adults) from across Lao PDR to measure IgG antibody titers against Vi polysaccharide and the experimental protein antigens, CdtB and HlyE. We measured the significance of the differences between antibody titers in adults and children and fitted models to assess the relationship between age and antibody titers. The median IgG titres of both anti-HylE and CdtB were significantly higher in children compared to adults (anti-HylE; 351.7 ELISA Units (EU) vs 198.1 EU, respectively; p<0.0001 and anti-CdtB; 52.6 vs 12.9 EU; p<0.0001). Conversely, the median anti-Vi IgG titer was significantly higher in adults than children (11.3 vs 3.0 U/ml; p<0.0001). A non-linear trend line fitted to the anti-CdtB and anti-HlyE IgG data identified a peak in antibody concentration in children <5 years of age. We identified elevated titers of anti-HlyE and anti-CdtB IgG in the serum of children residing in Lao PDR in comparison to adults. These antigens are associated with seroconversion after typhoid fever and may be a superior measure of disease burden than anti-Vi IgG. This approach is scalable and may be developed to assess the burden of typhoid fever in countries where the disease may be endemic, and evidence is required for the introduction of typhoid vaccines.

The epidemiology of typhoid fever in Lao People`s Democratic Republic is poorly defined. Estimating the burden of typhoid fever in endemic countries is complex due to the cost and limitations of population-based surveillance; serological approaches may be a more cost-effective alternative. ELISAs were performed on 937 serum samples (317 children and 620 adults) from across Lao PDR to measure IgG antibody titers against Vi polysaccharide and the experimental protein antigens, CdtB and HlyE. We measured the significance of the differences between antibody titers in adults and children and fitted models to assess the relationship between age and antibody titers. The median IgG titres of both anti-HylE and CdtB were significantly higher in children compared to adults (anti-HylE; 351.7 ELISA Units (EU) vs 198.1 EU, respectively; p<0.0001 and anti-CdtB; 52.6 vs 12.9 EU; p<0.0001). Conversely, the median anti-Vi IgG titer was significantly higher in adults than children (11.3 vs 3.0 U/ml; p<0.0001). A non-linear trend line fitted to the anti-CdtB and anti-HlyE IgG data identified a peak in antibody concentration in children <5 years of age. We identified elevated titers of anti-HlyE and anti-CdtB IgG in the serum of children residing in Lao PDR in comparison to adults. These antigens are associated with seroconversion after typhoid fever and may be a superior measure of disease burden than anti-Vi IgG. This approach is scalable and may be developed to assess the burden of typhoid fever in countries where the disease may be endemic, and evidence is required for the introduction of typhoid vaccines.