Foodborne Infections Research Articles

Inflammatory Responses Induced by the Monophasic Variant of Salmonella Typhimurium in Pigs Play a Role in the High Shedder Phenotype and Fecal Microbiota Composition.

Pigs infected with Salmonella may excrete large amounts of Salmonella, increasing the risk of spread of this pathogen in the food chain. Identifying Salmonella high shedder pigs is therefore required to mitigate this risk. We analyzed immune-associated markers and composition of the gut microbiota in specific-pathogen-free pigs presenting different shedding levels after an oral infection with Salmonella. Immune response was studied through total blood cell counts, production of anti-Salmonella antibodies and cytokines, and gene expression quantification. Total Salmonella shedding for each pig was estimated and hierarchical clustering was used to cluster pigs into high, intermediate, and low shedders. Gut microbiota compositions were assessed using 16S rRNA microbial community profiling. Comparisons were made between control and inoculated pigs, then between high and low shedders pigs. Prior to infection, high shedders had similar immunological profiles compared to low shedders. As soon as 1 day postinoculation (dpi), significant differences on the cytokine production level and on the expression level of several host genes related to a proinflammatory response were observed between high and low shedders. Infection with Salmonella induced an early and profound remodeling of the immune response in all pigs, but the intensity of the response was stronger in high shedders. In contrast, low shedders seroconverted earlier than high shedders. Just after induction of the proinflammatory response (at 2 dpi), some taxa of the fecal microbiota were specific to the shedding phenotypes. This was related to the enrichment of several functional pathways related to anaerobic respiration in high shedders. In conclusion, our data show that the immune response to Salmonella modifies the fecal microbiota and subsequently could be responsible for shedding phenotypes. Influencing the gut microbiota and reducing intestinal inflammation could be a strategy for preventing Salmonella high shedding in livestock. IMPORTANCE Salmonellosis remains the most frequent human foodborne zoonosis after campylobacteriosis and pork meat is considered one of the major sources of human foodborne infections. At the farm, host heterogeneity in pig infection is problematic. High Salmonella shedders contribute more significantly to the spread of this foodborne pathogen in the food chain. The identification of predictive biomarkers for high shedders could help to control Salmonella in pigs. The purpose of the present study was to investigate why some pigs become super shedders and others low shedders. We thus investigated the differences in the fecal microbial composition and the immune response in orally infected pigs presenting different Salmonella shedding patterns. Our data show that the proinflammatory response induced by S. Typhimurium at 1 dpi could be responsible for the modification of the fecal microbiota composition and functions observed mainly at 2 and 3 dpi and to the low and super shedder phenotypes.

Genomic Epidemiology and Multilevel Genome Typing of Australian Salmonella enterica Serovar Enteritidis.

Salmonella enterica serovar Enteritidis is one of the leading causes of salmonellosis in Australia. In this study, a total of 568 S. Enteritidis isolates from two Australian states across two consecutive years were analyzed and compared to international strains, using the S. Enteritidis multilevel genome typing (MGT) database, which contained 40,390 publicly available genomes from 99 countries. The Australian S. Enteritidis isolates were divided into three phylogenetic clades (A, B, and C). Clades A and C represented 16.4% and 3.5% of the total isolates, respectively, and were of local origin. Clade B accounted for 80.1% of the isolates which belonged to seven previously defined lineages but was dominated by the global epidemic lineage. At the MGT5 level, three out of five top sequence types (STs) in Australia were also top STs in Asia, suggesting that a fair proportion of Australian S. Enteritidis cases may be epidemiologically linked with Asian strains. In 2018, a large egg-associated local outbreak was caused by a recently defined clade B lineage prevalent in Europe and was closely related, but not directly linked, to three European isolates. Additionally, over half (54.8%) of predicted multidrug resistance (MDR) isolates belonged to 10 MDR-associated MGT-STs, which were also frequent in Asian S. Enteritidis . Overall, this study investigated the genomic epidemiology of S. Enteritidis in Australia, including the first large local outbreak, using MGT. The open MGT platform enables a standardized and sharable nomenclature that can be effectively applied to public health for unified surveillance of S. Enteritidis nationally and globally. IMPORTANCE Salmonella enterica serovar Enteritidis is a leading cause of foodborne infections. We previously developed a genomic typing database (MGTdb) for S. Enteritidis to facilitate global surveillance of this pathogen. In this study, we examined the genomic features of Australian S. Enteritidis using the MGTdb and found that Australian S. Enteritidis is mainly epidemiologically linked with Asian strains (especially strains carrying antimicrobial resistance genes), followed by European strains. The first large-scale egg-associated local outbreak in Australia was caused by a recently defined lineage prevalent in Europe, and three European isolates in the MGTdb were closely related but not directly linked to this outbreak. In summary, the S. Enteritidis MGTdb open platform is shown to be a potentially powerful tool for national and global public health surveillance of this pathogen.

Transmission Scenarios of Listeria monocytogenes on Small Ruminant On-Farm Dairies.

Listeria monocytogenes can cause severe foodborne infections in humans and invasive diseases in different animal species, especially in small ruminants. Infection of sheep and goats can occur via contaminated feed or through the teat canal. Both infection pathways result in direct (e.g., raw milk from an infected udder or fresh cheese produced from such milk) or indirect exposure of consumers. The majority of dairy farmers produces a high-risk product, namely fresh cheese made from raw ewe's and goat's milk. This, and the fact that L. monocytogenes has an extraordinary viability, poses a significant challenge to on-farm dairies. Yet, surprisingly, almost no scientific studies have been conducted dealing with the hygiene and food safety aspects of directly marketed dairy products. L. monocytogenes prevalence studies on small ruminant on-farm dairies are especially limited. Therefore, it was our aim to focus on three main transmission scenarios of this important major foodborne pathogen: (i) the impact of caprine and ovine listerial mastitis; (ii) the significance of clinical listeriosis and outbreak scenarios; and (iii) the impact of farm management and feeding practices.

Exploring the potential efficacy of phage therapy for biocontrol of foodborne pathogenic extensively drug-resistant Escherichia coli in gastrointestinal tract of rat model

AimThe emergence of extensively drug-resistant (XDR) Escherichia coli leaves little or no therapeutic options for the control of these foodborne pathogens. The goal is to isolate, characterize, and assess the potential efficacy of a bacteriophage in the treatment of an induced gastrointestinal tract infection. Main methodsSewage water was used to isolate phage phPE42. Transmission electron microscope was used for the visualization of phage morphology. Lysis profile, growth kinetics, and stability studies were determined. The ability of phage to eradicate biofilms was assessed by crystal violet staining, resazurin assay, compound bright field microscope, and confocal laser scanning microscope (CLSM). Moreover, the efficacy of phage phPE42 as a potential therapy was evaluated in a rat model. Key findingsA newly lytic Myoviridae phage phPE42 was isolated and exhibited broad coverage activity (48.6 %) against E. coli clinical isolates. It demonstrated favorable growth kinetics and relative stability under a variety of challenging conditions. The resazurin colorimetric assay and CLSM provided evidence of phage potential's ability to significantly (P < 0.05) decrease the viability of biofilm-embedded cells. The bacterial burden in animal faeces was effectively eradicated (P < 0.05) by oral administration of phage phPE42. Phage-treated rats exhibited a significant decrease in tissue damage with no signs of inflammation, necrosis, or erosion. Furthermore, phage therapy significantly (P < 0.05) reduced the expression level of the apoptotic marker caspase-3 and the inflammatory cytokine TNF-α. SignificanceTreatment with phage phPE42 is considered a promising alternative therapy for the control of severe foodborne infections spurred by pathogenic XDR E. coli.

Fluoroplast Doped by Ag2O Nanoparticles as New Repairing Non-Cytotoxic Antibacterial Coating for Meat Industry

Foodborne infections are an important global health problem due to their high prevalence and potential for severe complications. Bacterial contamination of meat during processing at the enterprise can be a source of foodborne infections. Polymeric coatings with antibacterial properties can be applied to prevent bacterial contamination. A composite coating based on fluoroplast and Ag2O NPs can serve as such a coating. In present study, we, for the first time, created a composite coating based on fluoroplast and Ag2O NPs. Using laser ablation in water, we obtained spherical Ag2O NPs with an average size of 45 nm and a ζ-potential of -32 mV. The resulting Ag2O NPs at concentrations of 0.001-0.1% were transferred into acetone and mixed with a fluoroplast-based varnish. The developed coating made it possible to completely eliminate damage to a Teflon cutting board. The fluoroplast/Ag2O NP coating was free of defects and inhomogeneities at the nano level. The fluoroplast/Ag2O NP composite increased the production of ROS (H2O2, OH radical), 8-oxogualnine in DNA in vitro, and long-lived active forms of proteins. The effect depended on the mass fraction of the added Ag2O NPs. The 0.01-0.1% fluoroplast/NP Ag2O coating exhibited excellent bacteriostatic and bactericidal properties against both Gram-positive and Gram-negative bacteria but did not affect the viability of eukaryotic cells. The developed PTFE/NP Ag2O 0.01-0.1% coating can be used to protect cutting boards from bacterial contamination in the meat processing industry.

Food safety knowledge attitude and practices of oncology nurses, in Lebanese hospitals

BackgroundCancer patients undergoing chemotherapy treatment, have a higher risk to foodborne infections as compared to other populations. Oncology nurses, having a direct significant contact with these patients, could be the first information source concerning food safety and play a pivotal role in reducing these risks. ObjectiveThis study aims to assess the level of knowledge regarding food safety among oncology nurses, as well as their attitudes and practices in private hospitals in Lebanon. MethodsA self-administered questionnaire was filled by Oncology nurses (n = 134) working in eighteen private hospitals in Lebanon located in Mount Lebanon (n = 11) and Beirut (n = 7). ResultsOverall, oncology nurses scored 76%, 95%, 86.9% and 83.4% on the knowledge, attitude, and practices questions, and overall composite knowledge, attitude, practices (KAP) score, respectively. Knowledge scores were higher among nurses holding a graduate degree (mean = 85; p < 0.05), and those who attended a training course (mean = 79; p < 0.05). Attitude scores of nurses who read brochures were higher (p < 0.001). Attending conferences on food safety showed statistically significant effect on better practice scores (p < 0.001). ConclusionAccordingly, the findings highlight the need to develop standardized food safety curriculum and training necessary to allow oncology nurses to contribute to the education of cancer patients and decrease their risk of foodborne infection.

Inhibitory interaction and pharmacological analyses of berries phenolics against Listeria monocytogenes virulent protein internalin B

Background: Traditional plants, their parts, and phytochemicals obtained from them are beneficial for human beings. They are used as potent antimicrobials, but very little research is conducted on the use of traditional medicine against food-borne infection. Different berry plants are rich in phenolic compounds and conventionally known to have many properties such as antioxidants, anti-carcinogenic, anti-inflammatory, anti-bacterial, and anti-diabetics. However, only limited polyphenols are known for their antilisterial effect. The present study aimed to explore the antimicrobial efficacy of phenolic compounds of berries for the treatment of food-borne infection caused by the bacteria Listeria monocytogenes. Materials and Methods: Molecular docking studies employing the SwissDOCK server were performed to evaluate the antimicrobial activity of phenolic compounds obtained from different varieties of berries. Internalin B (InlB), a virulence protein of L. monocytogenes was selected as a target. The absorption, distribution, metabolism, excretion, and toxicity profiling of each test ligand was done through the SwissADME tool. Results: Among all the test ligands, p-coumaric acid, epicatechins, chlorogenic acid, and quercetin showed better binding efficiency with the target protein InlB. The binding energy obtained for quercetin, p-coumaric acid, chlorogenic acid, and epicatechins was-8.93,-8.23,-8.18,-7.58, kcal/mol, respectively. Quercetin and p-coumaric acid were forming 4 H-bonds, whereas chlorogenic acid and epicatechins were forming 3-H bonds inside the binding pocket. Conclusion: In a nutshell, analyses indicated that identified ligands have the potential to block the virulent protein InlB of L. monocytogenes and help combat Listeria infection. These phenolic compounds could be a substitute for synthetic antimicrobials and can be used in food preservation and combat food-borne diseases. However, future in-depth in vitro and in vivo analysis is needed to get more information on these four phenolic ligands of berries.

Listeria monocytogenes isolated from raw milk: phenotypic and molecularcharacterization, pathogenicity testing, and multidrug resistance profiling

Foodborne infections are a worldwide public health emergency that actually impact a variety of disorders. In the current research, a total of 300 samples comprising raw milk (100),milk products (100), and chicken (100) were screened for detection of pathogenic Listeria species by using the USDA method. On conventional biochemical characterization, three isolates were identified as Listeria monocytogenes (from raw milk samples)indicating an overall prevalence of Listeria monocytogenes to the tune of 1%. All other samples comprising milk products and chicken samples (100) showed negativity for the presence of any of the Listeria species. Further, all three isolates were subjected to polymerase chain reaction (PCR) targeting genus-specific (prsA and iap) and species-specific gene (isp) in which all three were turn out positive for both the genes, endorsing their identification as Listeria monocytogenes. All three confirmed Listeria monocytogenes isolates were phenotypically assessed for in-vitro pathogenicity tests like hemolysis on 7% sheep blood agar, CAMP test, and PI-PLC assay. The results revealed their highly pathogenic nature. Subsequently, all these isolates were also assessed for their virulent nature by PCR, targeting the array ofmarkers including virulence-associated genes viz. hlyA, actA, plcA. The results endorsed pathogenic nature of all isolates showing amplification of all targeted virulence genes. The antibiotic resistance profiling revealed occurrence of multidrug-resistant pathogenic L. monocytogenes in foods of animal origin with maximum multiple antibiotic resistance (MAR) index of 0.6and a minimum MAR index of 0.48 in MDR, which is a matter of concern from public health point of view.

Evaluation of phage—antibiotic combinations in the treatment of extended-spectrum β-lactamase-producing Salmonella enteritidis strain PT1

Foodborne infections caused by Salmonella spp. are among the most common foodborne diseases in the world. We isolated a lytic phage against extended-spectrum beta-lactam producing S. Enteritidis strain PT1 derived from chicken carcass. Results from electronmicrography indicated that phiPT1 belonged to the family, Siphoviridae, in the order, Caudovirales. Phage phiPT1 was stable at temperatures from 4 °C to 60 °C and inactivated at 90 °C. phiPT1 retained a high titer from pH 4 to pH 10 for at least 1 h. Nevertheless, it displayed a significant decrease (p < 0.05) in titer at pH 11 and 12, with phage titers of 5.5 and 2.4 log10 PFU/mL, respectively. The latent time and burst size of phiPT1 were estimated to be 30 min and 252 PFU/infected cell, respectively. The virulence of phage phiPT1 was evaluated against S. Enteritidis strain PT1 at different MOIs. phiPT1 reduced Salmonella proliferation relative to the negative control (MOI 0) at all MOIs (P < 0.05). However, there is no significant difference among the MOIs (P > 0.05). The phage-antibiotic combination analysis (PAS) indicated that synergism was not detected at higher phiPT1 titer (1012 PFU/mL) with all tested antibiotics at all subinhibitory concentrations. However, synergistic activities were recorded at 0.25 × MIC of four tested antibiotics: cefixime, gentamicin, ciprofloxacin, and aztreonam in combination with phage at 104, 106 and 108 PFU/mL (ΣFIC ≤0.5). Synergism was detected for all antibiotics (0.1 × MIC) except meropenem and colistin in combination with phiPT1 at 104, 106 and 108 PFU/mL (ΣFIC ≤0.5). Synergism also displayed at the lowest concentrations of all antibiotics (0.01 MIC) in combination with phiPT1 at all titers except 1012 PFU/mL. Such characteristic features make phiPT1 to be a potential candidate for therapeutic uses.

Isolation and antimicrobial sensitivity test of Salmonella isolates from selected intensive dairy farms in Bishoftu town, Central Ethiopia

Salmonella is one of persisting foodborne pathogenic infection particularly food of animal origin including dairy cattle products. Accoringly a cross-sectional study was conducted from July to September 2021 to determine the prevalence and antibiotics resistant of Salmonella in Bishoftu town. To conduct the study 61 samples were collected randomly from the individual lactating cows. The Salmonella was recovered from the samples; conventional culture characterization of Salmonella was conducted by pre-enrichment on the buffered peptone water broth and enrichment in Rappaport- Vassiliadis (RV) broth, subsequently isolation was done on selective XLD and biochemical confirmation of Salmonella isolates. Finally, antibiotic sensitivity tests against the identified isolate were done by using eight drugs. Salmonella was isolated from 13/61 (21.3%, 95% CI: 11.3-31.3) of the total samples. Out of the 13 Salmonella isolates, 11/49 (22.4% 95% CI: 11.4-33.4) and 2/121 (16.7% 95% CI: 4.77-38.17) were isolated from milk cows and milk container respectively with no significance (P-value = 0.362). The isolates were susceptible to Ciprofloxacin, Penicillin and Vancomycin) were susceptible to the isolates, while, Streptomycin, Ampicillin, Tetracycline Rifampicillin and Cloxacillin) were resistant to the isolates. The effectiveness of such drugs like ciprofloxacin may be because they are not widely used in countries like Ethiopia and other African countries for animal’s treatment. 100% rate of resistant was recorded to Ampicillin, Chloramphenicol, Cloxacillin, Streptomycin and Amoxicillin. The study indicated the prevalence of Salmonella with high proportion of multiple antimicrobial resistance to the commercial used in the study area. Therefore, the government, farmers and other stakeholders should give concern for dairy farm hygiene and antibiotics uses in dairy farms.

Isolation and genomic characterization of Vmp-1 using Vibrio mimicus as the host: A novel virulent bacteriophage capable of cross-species lysis against three Vibrio spp.

Vibrio mimicus is a zoonotic pathogen that is widely distributed in aquatic habitats/environments (marine coastal water, estuaries, etc). The development of biocontrol agents for V. mimicus is imperative for the prevention and control of aquatic animal diseases and human food-borne infections. In this study, a broad-spectrum bacteriophage Vmp-1 was isolated from dealt aquatic product in a local market by double-layer agar plate method using V. mimicus CICC21613 as the host bacteria. Results indicated that Vmp-1, which belongs to the family Podoviridae, showed good pH tolerance (pH 3.0-12.0) and thermal stability (30-50°C). The optimal multiplicity of infection (MOI) of Vmp-1 was 0.001 for a 20-min incubation and 100-min lysis period. Vmp-1 effectively controlled V. mimicus CICC21613 in LBS model (MOI=0.0001, 0.001, 0.01, 0.1, 1) within 8h. The full length of the Vmp-1 genome was 43,312 bp, with average GC content of 49.5%, and a total of 44 protein-coding regions. This study provides a novel phage strain that has the highest homology with vB_VpP_HA5 (GenBank: OK585159.1, 95.96%) for the development of biocontrol agents for V. mimicus.

Antibacterial, Antioxidant, and in silico NADPH Oxidase Inhibition Studies of Essential Oils of Lavandula dentata against Foodborne Pathogens.

Food is always subjected to microbial infection and lipid peroxidation, which frequently leads to serious food intoxications. In the present study, essential oils (EOs) extracted from Lavandula dentata Moroccan species and its major component (linalool) were chemically characterized and their antioxidant potential and antibacterial properties against foodborne pathogenic bacteria were examined. EOs phytochemical profile was carried out using gas chromatography-mass spectrometry analysis (GC-MS). The antioxidant potential was evaluated, in vitro, by use of the β-carotene discoloration assay and in silico vs. NADPH oxidase enzymatic complex as an antioxidant marker. The antibacterial proprieties were assessed by use of minimal inhibitory concentration (MIC) and disc diffusion methods, against Gram (-) bacteria (Pseudomonas aeruginosa, Salmonella enterica, and Escherichia coli) and Gram (+) bacteria (Bacillus subtilis and Staphylococcus aureus). Linalool (49.71%) was the major component among the eighteen components identified in Lavandula dentate EO, followed by camphor (14.36%) and borneol (8.21%). The studied EO and linalool compounds showed important antioxidant activity through the β-carotene discoloration test with IC50 values of 35.72 ± 1.21 mg/mL and 30.32 ± 1.23 mg/mL, respectively. Among all the analyzed compounds of lavender EOs, thymol, carvacrol, and α-terpineol were the most active compounds against NADPH oxidase with a glide score of -6.483, -6.17, and -4.728 kcal/mol, respectively. 2D and 3D views showed the formation of hydrogen bonds between the most active compounds and the active site of NADPH oxidase. The antibacterial data showed a significant activity of Lavandula dentata essences against tested foodborne pathogenic bacteria, especially against S. aureus and B. subtilis. Linalool proved active toward the same bacteria and had closer activity to that of lavender essential oil. In light of the obtained findings, the essential oil of Lavandula dentata Moroccan species can be used in the packaging sector as a promising natural food conservative to limit lipid oxidation and treat foodborne infections.

Minimally processed fruits as vehicles for foodborne pathogens.

The consumption of minimally processed fruit (MPF) has increased over the last decade due to a novel trend in the food market along with the raising consumers demand for fresh, organic, convenient foods and the search for healthier lifestyles. Although represented by one of the most expanded sectors in recent years, the microbiological safety of MPF and its role as an emergent foodborne vehicle has caused great concern to the food industry and public health authorities. Such food products may expose consumers to a risk of foodborne infection as they are not subjected to prior microbial lethal methods to ensure the removal or destruction of pathogens before consumption. A considerable number of foodborne disease cases linked to MPF have been reported and pathogenic strains of Salmonella enterica, Escherichia coli, Listeria monocytogenes, as well as Norovirus accounted for the majority of cases. Microbial spoilage is also an issue of concern as it may result in huge economic losses among the various stakeholders involved in the manufacturing and commercialization of MPF. Contamination can take place at any step of production/manufacturing and identifying the nature and sources of microbial growth in the farm-to-fork chain is crucial to ensure appropriate handling practices for producers, retailers, and consumers. This review aims to summarize information about the microbiological hazards associated with the consumption of MPF and also highlight the importance of establishing effective control measures and developing coordinated strategies in order to enhance their safety.

Street Vended Juices as A Risk Factor of Microbial Diseases in District Mardan, Pakistan

In public spaces like streets and other outdoor areas, merchants prepare and sell foods and drinks for sale. The Food and Agriculture Organization estimates that 2.5 million individuals eat street food every day. Objective: To study the assessment of microbial contamination of juices vended in streets in District Mardan of Pakistan. Methods: 315 samples comprising juices of sugarcane, pomegranate, jaggery, plum, mango, banana and apples were aseptically collected from three Tehsils of district Mardan including Katlang, Takht Bhai and Mardan. Results: Analysis of the samples revealed that 96% of juices had high loads of bacterial pathogens such as Coliforms (96.82%), Staphylococcus (81.90%), Salmonella (64.76%). In Tehsil Katlang and Takht Bhai all collected samples were contaminated while in Mardan Tehsil 87.6% bacterial contamination was observed. Very high number of coliforms were observed in sugarcane, apple juices and Jaggery, Salmonella counts were highest 21.05x102 cfu/ml in Jagerry and Staphylococcus growth was highest in sugarcane 1.22x103 cfu/ml. Conclusions: It was noted that coliforms contamination is significantly higher as compared to other two bacteria indicating sewage water mixing in water used for preparation or handling of these juices. To prevent future food-borne infections, it is advised that frequent inspection of the quality of juices sold on the street be done.

Assessment of Hygienic conditions of Street Food Vendors and Identification of Hazardous points involved during Street Food Vending

The provision of safe and nutritious food is a fundamental human right that contributes to good health, efficiency, and provides a foundation for people' sustainable development and poverty reduction. Objectives: To analyze the sanitary conditions of street food sellers and to identify potential hazards during street food vending. Methods: A cross-sectional study was carried out. Between September and November 2013, 100 street food vendors in three heavily populated neighborhoods of Lahore (Ravi town, Data Ganj Baksh, and Shahdara town) were assessed using a questionnaire and a food safety checklist. For the production of safe street food, hazards were identified along the phases involved in street food selling. The SPSS software was used to analyze the data. Results: 89% of vendors lacked hygiene and proper clothing, and 71% did not wash their hands before food preparation. 36% of vendors were afflicted with various diseases. Only 27% of the vending units were sufficiently clean and well maintained. The biggest concern with unsanitary food served by street food sellers was that only 19% purchased raw items from trusted sources. Only 18% of respondents used separate utensils for raw and RTE food storage, while 49% did not. The presence of fungal growth (26%) indicated the source of food-borne infections. There were six primary points/steps in street food vendors where contamination and hazardous threats existed. Conclusions: Most street foods were found unsanitary and hazardous. The food vendors were mainly ignorant and uninformed about food safety. Basic GHP and HACCP related precautionary measures should be taken.

Prevalence of Salmonella in Sea Foods and Its Resistance to Drugs

Salmonella are non-spore forming, predominantly motile enterobacteria with peritrichous flagella (all around the cell body). They are intracellular pathogens causing illness. They usually invade only the gastrointestinal tract and cause Salmonellosis. Humans become infected most frequently through contaminated food or water. Sea foods are mostly associated with Salmonella infections. This study therefore was carried out to isolate Salmonella and determine the antibiotic sensitivity patterns of the Salmonella isolates from sea foods associated with food-borne diseases. These sea foods were obtained from three different selected markets within Port Harcourt Metropolis, Rivers State. A total of three (3) sea food samples were collected at random from each of the market. The samples were put through standard microbiological techniques. The result of total heterotrophic bacterial counts showed that Prawn from Mile 1 market had high count of 2.06x108 cfu/g while Crab from Creek Road market had the least count of 1.15x108 cfu/g. The result of total coliform count showed that Crab from Mile 1 market had the highest count of 2.86x106 cfu/g while Periwinkle from Creek Road market had the least count of 2.30x106 cfu/g. Also, the result of salmonella shigella count showed that Periwinkle from Mile 1 market had the least count of 0.76x105 cfu/g while Crab from Creek Road market had the highest count of 2.80x105 cfu/g. Characteristics of bacterial isolates from the sea foods showed that Proteus sp., Bacillus spp., Pseudomonas sp., Micrococcus sp., Staphylococcus aureus, Escherichia coli, and Salmonella spp. were present and identified from the samples. The result of the antibiotic susceptibility pattern of the Salmonella isolates showed that all the isolates were 100% susceptible to Tarivid, Peflacine, Septrine and Ciprofloxacin while they exhibited 100% intermediate sensitivity or resistance to the other antibiotics such as Ceporex, Nalidixic acid, Ampicillin, Gentamycin, Streptomycin, and Augmentin. The result of the multidrug resistance index of 3 (100%) of the 3 Salmonella isolates had a MAR index ≥ 0.2. The presence of these organisms in sea food could pose threat of food-borne infection as well as resistance to some commonly used antibiotics. Enforcement of existing laws associated with food storage, preparation and hygiene should be done in order to prevent or reduce these food-borne diseases such as salmonellosis.

Iron Deprivation by Oral Deferoxamine Application Alleviates Acute Campylobacteriosis in a Clinical Murine Campylobacter jejuni Infection Model.

The progressively rising food-borne Campylobacter jejuni infections pose serious health problems and socioeconomic burdens. Given that antibiotic therapy is not recommended for most campylobacteriosis patients, novel treatment options include strategies targeting iron homeostasis that impacts both C. jejuni virulence and inflammatory cell damage caused by toxic oxygen species. In our preclinical intervention study, we tested potential disease-alleviating effects upon prophylactic oral application of the iron-chelating compound desferoxamine (DESF) in acute murine campylobacteriosis. Therefore, microbiota-depleted IL-10-/- mice received synthetic DESF via the drinking water starting seven days before oral infection with C. jejuni strain 81-176. Results revealed that the DESF application did not reduce gastrointestinal pathogen loads but significantly improved the clinical outcome of infected mice at day 6 post-infection. This was accompanied by less pronounced colonic epithelial cell apoptosis, attenuated accumulation of neutrophils in the infected large intestines and abolished intestinal IFN-γ and even systemic MCP-1 secretion. In conclusion, our study highlights the applied murine campylobacteriosis model as suitable for investigating the role of iron in C. jejuni infection in vivo as demonstrated by the disease-alleviating effects of specific iron binding by oral DESF application in acute C. jejuni induced enterocolitis.

Surveillance of Human Cases of Salmonellosis, Campylobacteriosis, Listeriosis, and Hepatitis A in Campania (Southern Italy): Seven-Year Monitoring (2013–2019)

Foodborne infections cause illness and death every year worldwide. The aim of this study was to describe trends in 2013-2019 in the occurrence of human cases of salmonellosis, campylobacteriosis, listeriosis, and hepatitis A in the Campania region. Human case data were provided by the National Surveillance System of disease and were grouped by year, province, age group, and sex. Moreover, the number of people hospitalized was recorded. In the Campania region, the total number of confirmed human cases for the diseases investigated was 1924, with Hepatitis A and the Salmonellosis as the first most reported (1009 and 825 cases, respectively). The incidence rates of gastroenteritis under study were lower than those in Italy and European Union in the same period, with the exception of Hepatitis A whose incidence was higher than that recorded in Italy. Data on hospitalizations pointed out the onset of severe forms of infection also for listeriosis and campylobacteriosis, whose incidence was very low (27 and 63 cases, respectively). Unfortunately, no information on the foods implicated is available. Although probably underestimated, gastroenteritis due to foodborne agents still represents a burden in Campania, and continuous monitoring and implementation of the currently available regional surveillance system is required.

Effect of dietary β-glucan on intestinal microbial diversity and Salmonella vaccine immunogenicity and efficacy in pigs

Alternatives to antibiotics to improve animal performance, limit the negative impact of infectious disease, and/or reduce colonization with foodborne pathogens is a major focus of animal agricultural research. β-glucans, a generally-recognized-as-safe (GRAS) product derived from various sources, are used in swine and can serve as both a prebiotic and/or stimulant of the immune system given the expression of β-glucan receptors on immune cells. When supplied in the diet of nursery pigs, it is unclear how dietary additives, particularly those known to modulate immune status, impact immunogenicity and efficacy of mucosal-delivered vaccines. Salmonellosis is one of the most common bacterial foodborne infections in the United States, and consumption of contaminated pork is a major source of human infection. Reduction of foodborne Salmonella in pigs via vaccination is one strategy to reduce contamination risk and subsequently reduce human disease. We examined the ability of dietary β-glucan to modulate fecal microbial diversity, and immunogenicity and efficacy of a mucosally-delivered, live-attenuated Salmonella vaccine during the nursery period. While dietaryβ-glucan did modulate fecal alpha diversity, it did not alter the induction of peripheral Salmonella-specific IFN-γ secreting Tcells or Salmonella-specific IgA in oral fluids. In addition, vaccination reduced Salmonella enterica serovar Typhimurium fecal shedding and tissue colonization. Overall, addition of β-glucan to the nursery diet of pigs impacted the microbiota but did not alter mucosal vaccine immunogenicity and efficacy.

Türkiye’de 2015-2020 yılları arasında hayvansal orijinli Salmonella serovarlarının dağılımı

Salmonella is an important zoonotic microorganism and the most isolated among food-borne infections across the world, including Türkiye. The detection and identification of common serovars circulating in Türkiye can present very useful data in the fight against Salmonella, which threatens both animal and human health. This study aimed to determine the distribution and diversity of Salmonella serovars isolated from the samples sent to Bacteriological Diagnosis Laboratory of the Veterinary Control Central Research Institute. The serotyping results of a total of 1,047 Salmonella spp. strains isolated between 2015 and 2020 were retrospectively evaluated. After confirming that the samples isolated were Salmonella spp. according to ISO 6579, identification at the species level was carried out by serotyping with the slide agglutination test. A total of 19 serogroups and 75 Salmonella serovars were detected. The most commonly isolated Salmonella serovar was Salmonella Infantis (40.5%), followed by Salmonella Enteritidis (12.9%), Salmonella Abony (4.3%), Salmonella Kentucky (4.2%), Salmonella Typhimurium (4%), Salmonella Liverpool (2.4%), and other serovars (31.3%). The most commonly identified serogroups were C1 (48.2%), D1 (14.4%), B (12.4%), C3 (7.8%), and E4 (4.2%). According to animal species, the most common serovar was Salmonella Infantis in chickens, Salmonella Montevideo in calves, Salmonella Darle in tortoises, Salmonella Typhimurium in lamb and Salmonella Hessarek in wild birds.