Prevalence, antibiotic resistance, and genomic characterisation of spp. in retail chicken in Hanoi, Vietnam.

spp. are a leading cause of bacterial foodborne zoonosis worldwide, with poultry meat and products recognised as a significant source of human infection. In Vietnam there are few data regarding the occurrence, antimicrobial resistance, and genomic diversity of in poultry and poultry meat.

Early vaccination of laying hens with the live bivalent vaccine AviPro™ Salmonella DUO results in successful vaccine uptake and increased gut colonization.

Introduction: Enteritidis and Typhimurium are the two most clinically important zoonotic serovars and vaccination of breeding and laying hens affords effective control. The use of live vaccines has proven beneficial for a number of reasons, including ease of application, protection from the first day of life onwards and initiation of a strong local immune response. Live vaccines can be applied in the drinking water from the first day of life onwards, but some rearers choose to wait until the end of the first week to ensure sufficient water consumption.

Contrasting long-term dynamics of antimicrobial resistance and virulence plasmids in Typhimurium from animals.

Plasmids are mobile elements that can carry genes encoding traits of clinical concern, including antimicrobial resistance (AMR) and virulence. Population-level studies of , including and , indicate that plasmids are important drivers of lineage expansions and dissemination of AMR genes. Typhimurium is the second most common cause of salmonellosis in humans and livestock in the UK and Europe.

In-depth farm investigations and an exploratory risk factor analysis for the presence of Salmonella on broiler farms in Great Britain.

Salmonella is a major cause of foodborne illness across Europe but there has been little recent research on its control in broiler production in Great Britain. Investigations of Salmonella presence on 20 broiler farms and a separate exploratory risk factor analysis involving 36 Salmonella-positive farms and 22 Salmonella-negative farms were carried out to investigate Salmonella contamination and control on broiler farms in Great Britain. Sources of Salmonella persistence on farm and potential risk factors for on-farm contamination were identified, enabling provision of up-to-date advice on Salmonella control to farmers.

Pilot Investigation of Anti- Antibodies in Oral Fluids from Typhimurium Vaccinated and Unvaccinated Swine Herds.

Oral fluid (OF) can be a simple, cheap and non-invasive alternative to serum or meat juice for the diagnosis and surveillance of important pathogens in pigs. This study was conducted on four Typhimurium-positive farrow-to-finish pig farms: two -vaccinated (V) and two non-vaccinated (NV). Gilts and sows in the V farms were vaccinated with a live, attenuated vaccine prior to farrowing.

Investigating the Association Between the Caecal Microbiomes of Broilers and Burden.

One of the major transmission routes for the foodborne bacterial pathogen is undercooked poultry meat, contaminated from intestinal contents during processing. In broilers, can grow to very high densities in the caeca, and is often considered to be a commensal or an opportunistic pathogen in poultry. Reduction of caecal loads of may assist in lowering incidence rates of food poisoning.

An Chicken Gut Model Demonstrates Transfer of a Multidrug Resistance Plasmid from to Commensal .

The chicken gastrointestinal tract is richly populated by commensal bacteria that fulfill various beneficial roles for the host, including helping to resist colonization by pathogens. It can also facilitate the conjugative transfer of multidrug resistance (MDR) plasmids between commensal and pathogenic bacteria which is a significant public and animal health concern as it may affect our ability to treat bacterial infections. We used an chemostat system to approximate the chicken cecal microbiota, simulate colonization by an MDR pathogen, and examine the dynamics of transfer of its MDR plasmid harboring several genes, including the extended-spectrum beta-lactamase We also evaluated the impact of cefotaxime administration on plasmid transfer and microbial diversity.

A novel O-linked glycan modulates Campylobacter jejuni major outer membrane protein-mediated adhesion to human histo-blood group antigens and chicken colonization.

Campylobacter jejuni is an important cause of human foodborne gastroenteritis; strategies to prevent infection are hampered by a poor understanding of the complex interactions between host and pathogen. Previous work showed that C. jejuni could bind human histo-blood group antigens (BgAgs) in vitro and that BgAgs could inhibit the binding of C.

Cj1136 is required for lipooligosaccharide biosynthesis, hyperinvasion, and chick colonization by Campylobacter jejuni.

Campylobacter jejuni is a major cause of bacterial food-borne enteritis worldwide, and invasion into intestinal epithelial cells is an important virulence mechanism. Recently we reported the identification of hyperinvasive C. jejuni strains and created a number of transposon mutants of one of these strains, some of which exhibited reduced invasion into INT-407 and Caco-2 cells.

Longitudinal molecular epidemiological study of thermophilic campylobacters on one conventional broiler chicken farm.

Improved understanding of the ecology and epidemiology of Campylobacter in the poultry farm environment is key to developing appropriate farm-based strategies for preventing flock colonization. The sources of Campylobacter causing broiler flock colonization were investigated on one poultry farm and its environment, from which samples were obtained on three occasions during each of 15 crop cycles. The farm was adjacent to a dairy farm, with which there was a shared concreted area and secondary entrance.

Campylobacter colonization of the chicken induces a proinflammatory response in mucosal tissues.

Campylobacter jejuni is a major cause of human inflammatory enteritis, but colonizes the gastrointestinal tract of poultry to a high level in a commensal manner. In vitro, C. jejuni induces the production of cytokines from both human and avian-model epithelial cell and macrophage infections.

Topology and patch-clamp analysis of the sodium channel in relationship to the anti-lipid a antibody in campylobacteriosis.

An infecting strain VLA2/18 of Campylobacter jejuni was obtained from an individual with campylobacteriosis and used to prepare chicken sera by experimental infection to investigate the role of serum anti-ganglioside antibodies in Guillain-Barré syndrome. Both sera of the patient and chicken contained anti-ganglioside antibodies and anti-Lipid A (anti-Kdo2-Lipid A) antibodies directed against the lipid A portion of the bacterial lipooligosaccharide. The anti-Kdo2-Lipid A activities inhibited voltage-gated Na (Nav) channel of NSC-34 cells in culture.

Host-pathogen interactions in Campylobacter infections: the host perspective.

Campylobacter is a major cause of acute bacterial diarrhea in humans worldwide. This study was aimed at summarizing the current understanding of host mechanisms involved in the defense against Campylobacter by evaluating data available from three sources: (i) epidemiological observations, (ii) observations of patients, and (iii) experimental observations including observations of animal models and human volunteer studies. Analysis of available data clearly indicates that an effective immune system is crucial for the host defense against Campylobacter infection.

A temperature-regulated Campylobacter jejuni gluconate dehydrogenase is involved in respiration-dependent energy conservation and chicken colonization.

Campylobacter jejuni is a gastrointestinal pathogen of humans but can asymptomatically colonize the avian gut. C. jejuni therefore grows at both 37 degrees C and 42 degrees C, the internal temperatures of humans and birds respectively.

Human and chicken antibodies to gangliosides following infection by Campylobacter jejuni.

Campylobacteriosis is frequently associated with Guillain-Barré syndrome. Poultry are frequently highly colonized with Campylobacter jejuni and are a major foodborne vehicle for campylobacteriosis. In this study, high titer anti-GM1 antibodies were found in the serum of a laboratory worker who developed campylobacteriosis.

Role of intimin-tir interactions and the tir-cytoskeleton coupling protein in the colonization of calves and lambs by Escherichia coli O157:H7.

Intimin facilitates intestinal colonization by enterohemorrhagic Escherichia coli O157:H7; however, the importance of intimin binding to its translocated receptor (Tir) as opposed to cellular coreceptors is unknown. The intimin-Tir interaction is needed for optimal actin assembly under adherent bacteria in vitro, a process which requires the Tir-cytoskeleton coupling protein (TccP/EspF(U)) in E. coli O157:H7.

Cytolethal distending toxin (CDT)-negative Campylobacter jejuni strains and anti-CDT neutralizing antibodies are induced during human infection but not during colonization in chickens.

The cytolethal distending toxin (CDT) of Campylobacter jejuni was detectable, using an in vitro assay, in most but not all of 24 strains tested. The reason for the absence of toxin activity in these naturally occurring CDT-negative C. jejuni strains was then investigated at the genetic level.