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Simple Summary: In this study, we investigated the role of microRNA-215 (miR-215) during Salmonella Typhimurium (S. Typhimurium) infection using a combination of in vivo porcine models and in vitro epithelial cell lines. Several dysregulated microRNAs (miRNAs) were identified in the infected porcine ileum, with miR-215 showing significant downregulation. Gain-of-function experiments in porcine (IPEC-J2) and human (HT29) intestinal epithelial cells revealed that miR-215 overexpression inhibits ubiquitination, subsequently downregulating key host immune response pathways such as autophagy and inflammasome activation. Our findings demonstrate that miR-215, downregulated during Salmonella Typhimurium infection in porcine ileum, plays a crucial role in regulating the host immune response by targeting proteins involved in ubiquitination, thereby influencing inflammasome activation and autophagy. The host response to S. Typhimurium infection can be post-transcriptionally regulated by miRNAs. In this study, we investigated the role of miR-215 using both in vivo porcine infection models and in vitro intestinal epithelial cell lines. Several miRNAs were found to be dysregulated in the porcine ileum during infection with wild-type and SPI2-defective mutant strains of S. Typhimurium, with some changes being SPI2-dependent. Notably, miR-215 was significantly downregulated during infection. To explore its functional role, gain-of-function experiments were performed by transfecting porcine intestinal epithelial cells (IPEC-J2) with a miR-215-5p mimic, followed by label-free quantitative (LFQ) proteomic analysis. This analysis identified 157 proteins, of which 35 were downregulated in response to miR-215 overexpression, suggesting they are potential targets of this miRNA. Among these, E2 small ubiquitin-like modifier (SUMO)-conjugating enzyme UBC9 and E3 ubiquitin-ligase HUWE1 were identified as key targets, both of which are upregulated during S. Typhimurium infection. The miR-215-mediated downregulation of these proteins resulted in a significant decrease in overall ubiquitination, a process crucial for regulating inflammasome activation and autophagy. Consistently, inflammasome markers caspase 1 (CASP1) and apoptosis-associated speck-like protein containing a CARD (ASC), as well as autophagy markers microtubule-associated protein 1A/1B-light chain 3 (LC3B) and Ras-related protein Rab-11 (RAB11A), showed decreased expression in miR-215 mimic-transfected and infected IPEC-J2 cells. To further validate these findings, human intestinal epithelial cells (HT29) were used as a complementary model, providing additional insights into conserved immune pathways and extending the observations made in the porcine system. Overall, our findings demonstrate that miR-215 plays a significant role in modulating host inflammasome activation and autophagy by targeting proteins involved in ubiquitination during S. Typhimurium infection. [ABSTRACT FROM AUTHOR]

Background/Objectives: This study aims to characterize antibiotic resistance (AR) and virulence markers in Salmonella spp. isolated from Romanian outpatients' stool samples. Methods: In 2019, community-acquired Salmonella strains were collected and identified using MALDI-TOF mass spectrometry, antibiotic susceptibility profiles have been determined with the MicroScan system, and soluble virulence factors were evaluated using specific culture media, while biofilm formation was quantified in 96-well plates. Molecular analysis targeted resistance genes for β-lactams (e.g., blaTEM and blaSHV); tetracyclines (e.g., tet(A)); sulphonamides; and quinolones, as well as virulence genes (e.g., invA, spvC, pldA, and held). Whole-genome sequencing (WGS) was performed on 19 selected isolates. A silver nanoparticles (AgNPsol) alternative to conventional antibiotics was tested for effectiveness against multidrug-resistant (MDR) isolates. Results: From the total of 309 Salmonella isolates (65.05% from children under 4 years of age) belonging to four subtypes and four serovars, 27.86% showed resistance to at least one antibiotic, most frequently to tetracycline, ampicillin, and piperacillin. The strains frequently expressed haemolysin (67%), aesculinase (65%), and gelatinase (62%). Resistance to trimethoprim-sulfamethoxazole was encoded by the sul1 gene in 44.83% of the strains and to tetracyclines by the tet(A) gene (59.52%). The ESBL genes blaTEM, blaSHV, and blaCTX-M were detected by PCR in 16.18%, 2.91%, and 0.65% of the strains, respectively. Additionally, 98.63% of the strains carried the invA marker, with notable positive associations between blaSHV, qnrB, and sul1 with spvC. Conclusions: The present findings revealed significant patterns in Salmonella isolates, subtypes, serovars, AR, and virulence, emphasising the need for continuous surveillance of Salmonella infections. Additionally, the potential of AgNPs as an alternative treatment option was demonstrated, particularly for paediatric S. enterica infections. [ABSTRACT FROM AUTHOR]

Background: The sexual transmissibility of enteric pathogens, including Salmonella spp., has been described in men who have sex with men (MSM). However, the factors seen in MSM with Salmonella spp. are poorly understood. Method: We aimed to systematically review the literature to explore any factors seen in MSM with Salmonella spp. (MSM). We searched six databases—Medline, PubMed, CINAHL, Embase, Emcare, and Global Health—in April 2024 for manuscripts which contained primary peer-reviewed data in English and the measurement of any risk factors observed in MSM with Salmonella spp. This review was registered on PROSPERO (CRD42023472864). Results: Eleven manuscripts were included in the final review and highlighted demographic (living with HIV), behavioural (oral–anal sex, receptive and penetrative anal sex, hand licking to stimulate their partner, group sex, non-condom use), and biological (co-infection with CMV, Mycobacterium avium complex, Strongyloides stercoralis, Blastocystis hominis, Klebsiella spp. Herpes simplex virus, Cytomegalovirus, Cryptosporidium, Histoplasmosis, Shigella spp.; previous infection with Treponema pallidum, Neisseria gonorhoeae, Chlamydia trachomatis and hepatitis B; and antimicrobial treatment failure) factors seen in MSM with Salmonella spp. Conclusion: Despite a limited number of manuscripts and individuals, this review highlighted some potential demographic, behavioural, and biological factors implicated in the transmission of Salmonella spp. in MSM. These data will provide insights for future guidelines, public health control strategies, and research. [ABSTRACT FROM AUTHOR]

Salmonella is one of the main foodborne pathogens. Irrational antibiotic management has led to an increase in the incidence of multidrug-resistant strains. Bacteriophages may be an alternative method of food biopreservation and contribute to reducing the number of food poisonings requiring pharmacotherapy. This study aimed to isolate a bacteriophage (phage) targeting indigenous multidrug-resistant (MDR) Salmonella strains, followed by their biological, morphological, and genomic characterization. In this study we isolated Salmonella phage KKP_3822, targeting MDR Salmonella Manchester strain KKP 1213. Salmonella phage KKP_3822 retained high activity in the temperature range from −20 °C to 40 °C and active acidity from pH 3 to 11. Temperatures of 70 °C and 80 °C and extreme pH values (2 and 12) significantly reduced the phage titer. Its activity decreased proportionally to the time of UV exposure. Genome analysis (linear dsDNA with a length of 114,843 bp) revealed the presence of 27 tRNA genes. Proteins encoded by the vB_Sen-IAFB3822 phage were divided into functional modules related to (i) phage structure/assembly, (ii) DNA replication/modification/regulation, (iii) phage lysis, and (iv) DNA packaging into the capsid. No genes associated with antibiotic resistance or integration into the host genome, markers of temperate bacteriophages, were annotated in the Salmonella phage KKP_3822 genome. Based on morphological features and whole-genome sequence analysis, the newly isolated Salmonella phage KKP_3822 shows the greatest similarity to representatives of tailed phages from the Caudoviricetes class, Demerecviridae family, and Epseptimavirus genus. Genome analysis confirmed the virulent nature of the Salmonella phage KKP_3822, making it a potential candidate for food biocontrol. [ABSTRACT FROM AUTHOR]

Simple Summary: Salmonella is a significant foodborne disease affecting the poultry industry and human health worldwide. Understanding the protective role of the intestinal mucosal immune response to Salmonella infection is critical to developing immune-based strategies to control Salmonella infection in chickens. Therefore, this study was conducted to determine the kinetics of intraepithelial lymphocytes (IELs) and their role in Salmonella enterica serovar Typhimurium (S. Typhimurium) infection. The results revealed that various IEL subtypes respond to Salmonella infection, highlighting their essential role during infection. At day 21 of age, Ross-308 broilers were orally gavaged with 7.5 × 106 CFU/mL S. Typhimurium (n = 30), and another 30 birds were kept as the control. The body weight of birds was recorded on days 0, 2, 7, and 14 days post-infection (dpi) to calculate body weight gains (BWGs). At each time point, seven birds per group were euthanized for sample collection to acquire IELs and lymphocytes from the ileum and spleen for flow cytometric analysis. A reduction in BWGs of the infected groups compared to the control group was observed only at 2 dpi. Additionally, there were no changes in the expression of IFN-γ, IL-1β, and TNF-α in the ileum at 2 and 7 dpi. The number of IELs increased significantly following Salmonella infection in the ileum at 2 and 7 dpi without any changes in spleen lymphocytes. The increase in the total number of IELs was derived from the elevated numbers of conventional CD8αβ+TCRαβ+ and natural IEL populations (CD4−CD8−TCRαβ+, CD8αα+TCRαβ+, TCRγδ+, non-T cells (TCRneg, and iCD8α cells)). The increase in regulatory IELs and the stable expression of proinflammatory cytokine genes during the first week of infection suggests the potential role of IELs in modulating intestinal inflammation. [ABSTRACT FROM AUTHOR]

Simple Summary: This study addresses the issue of the detection of harmful bacteria (Salmonella and other hydrogen sulphide-positive bacteria) present in fish for consumption, which may arise from contaminated water or improper handling. The aim is to compare two methods for identifying these bacteria in the digestive content of fish from the Macaronesian region. A total of 59 samples were analysed. Salmonella was not detected, but other bacteria were identified (47), the most common being Enterobacter. This study revealed that the new MALDI-TOF MS method is faster and more accurate than the traditional API method, showing high concordance in the identification of bacteria. These findings are important because they highlight the limitations of older techniques and emphasise the importance of using more effective methods to ensure food safety. By improving the identification of potentially harmful bacteria, this research can help protect public health and improve safety standards in the food industry. Salmonella spp. are known pathogens in fish, with their presence potentially resulting from the contamination of the aquatic environment or improper handling. Accurate bacterial identification is crucial across various fields, including medicine, microbiology, and the food industry, and thus a range of techniques are available for this purpose. In this study, Salmonella spp. and other hydrogen sulphide-positive bacteria were investigated in the digestive contents of fish destined for consumption from the Atlantic area of Macaronesia. Two identification techniques were compared: the traditional API method and the MALDI-TOF MS technique. For the identification of Salmonella spp. carriers, 59 samples were processed following ISO 6579–1:2017. A total of 47 strains of Gram-negative bacilli were obtained. No Salmonella spp. isolates were detected. The most frequent genus was Enterobacter (76.50%), followed by Shewanella (10.63%). The MALDI-TOF MS technique showed a high concordance with the API technique, with 72.34% concordance at the species level. Both techniques demonstrated a high degree of concordance in the identification of Enterobacter cloacae, with 87.23% genus-level concordance and 12.76% non-concordant identifications. This study highlights the limitations of the API technique and the speed and precision of MALDI-TOF MS. The identified bacteria could pose a health risk to humans. [ABSTRACT FROM AUTHOR]

Simple Summary: This study reports cases of esophagitis and ingluvitis caused by Salmonella Typhimurium in passerine birds seized from illegal trade, highlighting its relevance to One Health. While few studies document salmonellosis in passerines, this investigation aimed to describe the disease in these species, identify the pathogen in their environment, and assess antimicrobial resistance profiles. Necropsy revealed necrotic lesions in the crop and esophagus, from which Salmonella spp. was isolated. The same pathogen was also found in the quarantine environment. Both environmental and animal strains exhibited resistance to multiple antibiotic classes. Serotyping identified the pathogen as the Typhimurium serovar in two birds. This study underscores the need for understanding circulating pathogens in wildlife to develop mitigation strategies, prevent zoonotic transmission, and address antimicrobial resistance. The occurrence of esophagitis and ingluvitis caused by Salmonella Typhimurium in passerines seized from illegal wildlife trafficking is described. This illegal activity causes stress and leads to lowered immunity in the birds. Additionally, inadequate hygiene conditions predispose the birds to diseases such as salmonellosis. Few studies report the occurrence of Salmonella-induced lesions in the esophagus and crop of passerines; therefore, this study aimed to describe the disease in birds of the genus Sporophila, as well as to investigate the presence of the bacterium in the environment and determine the antimicrobial resistance profile of the isolated bacteria. Three birds of the genus Sporophila were necropsied. In the esophagus and crop, yellowish plaques corresponding to necrosis with bacterial aggregates were observed. Salmonella spp. was isolated from these lesions, with genus confirmation via MALDI-TOF mass spectrometry. Environmental samples were collected from the enclosures and cages where the animals were quarantined, and the same bacterium was isolated. In two birds, the serotype S. Typhimurium was identified. Antibiograms performed on the strains from the birds and the environment revealed resistance to antibiotics in the classes of penicillins, sulfonamides, aminoglycosides, monobactams, tetracyclines, and first and third-generation cephalosporins. To the authors' knowledge, this is the first report of this agent causing death in Sporophila due to esophagitis and ingluvitis. It is also the first report of salmonellosis in three species of passerines in Brazil. The study underscores the importance of understanding the pathogens circulating in wild animals, especially within the context of One Health. [ABSTRACT FROM AUTHOR]

Salmonella is a significant zoonotic foodborne pathogen, and the global spread of multidrug-resistant (MDR) strains poses substantial challenges, necessitating alternatives to antibiotics. Among these alternatives, vaccines protect the community against infectious diseases effectively. This review aims to summarize the efficacy of developed Salmonella vaccines evaluated in various animal hosts and highlight key transitions for future vaccine studies. A total of 3221 studies retrieved from Web of Science, Google Scholar, and PubMed/Medline databases between 1970 and 2023 were evaluated. One hundred twenty-seven qualified studies discussed the vaccine efficacy against typhoidal and nontyphoidal serovars, including live-attenuated vaccines, killed inactivated vaccines, outer membrane vesicles, outer membrane complexes, conjugate vaccines, subunit vaccines, and the reverse vaccinology approach in different animal hosts. The most efficacious vaccine antigen candidate found was recombinant heat shock protein (rHsp60) with an incomplete Freund's adjuvant evaluated in a murine model. Overall, bacterial ghost vaccine candidates demonstrated the highest efficacy at 91.25% (95% CI = 83.69–96.67), followed by the reverse vaccinology approach at 83.46% (95% CI = 68.21–94.1) across animal hosts. More than 70% of vaccine studies showed significant production of immune responses, including humoral and cellular, against Salmonella infection. Collectively, the use of innovative methods rather than traditional approaches for the development of new effective vaccines is crucial and warrants in-depth studies. [ABSTRACT FROM AUTHOR]

Salmonella is among the causative agents for diarrhea worldwide, but its risk factors in Tanzanian children are poorly understood. A hospital-based cross-sectional study was conducted in Moshi, Kilimanjaro region, from July 2020 to November 2022 among children under five admitted with diarrhea. A questionnaire was administered to all parents/caretakers of the enrolled children. Logistic regression was utilized to analyze the risk factors, with significance at p < 0.05. A total of 306 children were enrolled in the study. The median age was 13.8 months (IQR 8.4–21.8). The majority (58.5%) were males, and 59.5% were from rural areas. Salmonella was identified in eight (2.6%) stool samples, with a higher prevalence in urban than rural areas (4.8% vs. 1.1%; p-value = 0.044). The significant risk factors associated with Salmonella infection among the children included consuming raw milk (adjusted OR = 30.19; 95% CI: 3.94–231.46), using infant formula (adjusted OR = 15.78; 95% CI: 2.98–83.56), undisclosed household income (adjusted OR = 9.98; 95% CI: 2.46–40.12), purchasing eggs direct from the farms (adjusted OR = 7.58; 95%CI: 1.31–43.96), and contact with chickens (adjusted OR = 6.49; 95%CI: 1.25–33.59). These findings highlight the need for targeted interventions to improve food safety, hygiene practices, and socioeconomic conditions. [ABSTRACT FROM AUTHOR]

Salmonella remains a significant foodborne pathogen globally with S. Typhimurium presenting as a frequently occurring serovar. This study aimed to characterize 67 S. Typhimurium isolates from humans, food, farms, and slaughterhouses collected in Singapore from 2016 to 2017. Using whole-genome sequencing analysis, the isolates were found to belong to either ST19 (n = 33) or ST36 (n = 34). ST36 predominated in human intestinal and chicken isolates, while human extra-intestinal and non-chicken food isolates belonged to ST19. Plasmids were predicted in 88.1% (n = 59) of the isolates with the most common incompatibility group profiles being IncFIB(S), IncFII(S) and IncQ1. IncFIB(S) (adjusted p-value < 0.05) and IncFII(S) (adjusted p-value < 0.05) were significantly more prevalent in ST19 isolates, while Col156 (adjusted p-value < 0.05) was more significantly found in ST36 isolates. ST36 isolates exhibited higher resistance to multiple antibiotic classes such as penicillins, phenicols, folate pathway inhibitors, aminoglycosides, β-lactam/β-lactamase inhibitor combinations, tetracyclines, and fluoroquinolones. Phylogenetics analysis suggested potential shared routes of transmission among human, chicken, farm and slaughterhouse environments. Taken together, this study offers a cross-sectional epidemiological insight into the genomic epidemiology and antimicrobial landscape of S. Typhimurium isolates in Singapore, informing strategies for future public health and food safety surveillance. [ABSTRACT FROM AUTHOR]

Simple Summary: Salmonellosis represents a considerable public and animal health concern. Cattle and particularly calves can be affected by this infection, which can cause a variety of clinical problems. At present, data about the diffusion of Salmonella spp. in dairy cattle farms of northern Italy are scarce. In this context, this study aims to conduct a retrospective survey on the presence of Salmonella serotypes in dairy cattle farms in the Cremona and Mantua provinces of the Lombardy Region (northern Italy). The results highlight that in most cases, Salmonella spp. was detected in the carcasses or organs of calves and that its presence was widely distributed on the farm. Finally, the analyses of antimicrobial resistance patterns place the attention on the spread of multi-drug resistant Salmonella strains. The presence of Salmonella spp. in dairy cattle farms poses a major risk to animal health and welfare. This study focused on Salmonella detection in dairy farms located in the Cremona and Mantua provinces (northern Italy) in samples collected and submitted to laboratories in 2021–2022. A total of 2710 samples from different sources, including calf carcasses/organs (n = 128), rectal swabs (n = 1937), feces (n = 390), bulk milk (n = 93), and overshoes/swabs (n = 127) for environmental sampling, were analyzed for the presence of Salmonella spp. and were included in the present study. Our results indicate that Salmonella was most commonly firstly identified from calf carcasses and organs (61.67%) and that the serotypes most frequently detected in dairies were S. Dublin (38.33%), S. Typhimurium (23.33%), and S. Typhimurium monophasic variant (14.17%). The most common pathological findings in calf carcasses were enteritis, hepatosplenomegaly, and pneumonia. The antimicrobial resistance pattern analyzed using the MIC assay of 51 Salmonella isolates revealed the presence of multi-resistant strains, which pose a major risk to public and animal health. [ABSTRACT FROM AUTHOR]

Nontyphoidal salmonellosis is an important foodborne and zoonotic infection that causes significant global public health concern. Diverse serovars are multidrug-resistant and encode several virulence indicators; however, little is known on the role prophages play in driving these traits. Here, we extracted prophages from seventy-five Salmonella genomes which represent the fifteen important serovars in the United Kingdom. We analyzed the intact prophages for the presence of virulence genes and established their genomic relationships. We identified 615 prophages from the Salmonella strains, from which 195 prophages are intact, 332 are incomplete, while 88 are questionable. The average prophage carriage was found to be 'extreme' in S. Heidelberg, S. Inverness, and S. Newport (10.2–11.6 prophages/strain), 'high' in S. Infantis, S. Stanley, S. Typhimurium, and S. Virchow (8.2–9.0 prophages/strain), 'moderate' in S. Agona, S. Braenderup, S. Bovismorbificans, S. Choleraesuis, S. Dublin, and S. Java (6.0–7.8 prophages/strain), and 'low' in S. Javiana and S. Enteritidis (5.8 prophages/strain). Cumulatively, 61 virulence genes (1500 gene copies) were detected from representative intact prophages and linked to Salmonella delivery/secretion system (42.62%), adherence (32.7%), magnesium uptake (3.88%), regulation (5%), stress/survival (1.6%), toxins (10%), and antivirulence (1.6%). Diverse clusters were formed among the intact prophages and with bacteriophages of other enterobacteria, suggesting different lineages and associations. Our work provides a strong body of data to support the contributions diverse prophages make to the pathogenicity of Salmonella, including thirteen previously unexplored serovars. [ABSTRACT FROM AUTHOR]

Salmonella enterica subsp. enterica serovar Enteritidis (S. Enteritidis) is one of the leading causes of foodborne infections associated with broilers and laying hens. Portugal has had the lowest notification rates of salmonellosis in recent years, due to the vaccinations of layer and breeder flocks and strict compliance with biosecurity measures. However, data about the genetic diversity of S. Enteritidis in Portugal are scarce. In this study, 102 S. Enteritidis isolates selected from human (n = 63) and non-human sources (n = 39) were characterized by serotyping, antimicrobial susceptibility, and whole genome sequencing. The S. Enteritidis population was mainly resistant to fluoroquinolones, and a sole isolate showed resistance to extended-spectrum cephalosporins. ST11 was the most frequent sequence type, and three novel STs from human isolates (ST9236, ST4457, and ST9995) were assigned. Several Salmonella pathogenic islands (SPI) and Putative SPI were present in the genomes, namely SPI-1, 2, 3, 4, 5, 9, 10, 12, 13, and 14, C63PI, CS54_island, and 170 virulence genes were identified. The phylogenetic analysis revealed that strains from Portugal are genetically heterogeneous regarding sample type, collection date, and genetic content. This study increases the available data, essential to a better characterization of strains in a global context. [ABSTRACT FROM AUTHOR]

In recent years, Salmonella enterica subsp. enterica serovar Mbandaka (S. Mbandaka) has been increasingly isolated from laying hens and shell eggs around the world. Moreover, this serovar has been identified as the causative agent of several salmonellosis outbreaks in humans. Surprisingly, little is known about the characteristics of this emerging serovar, and therefore, we investigated antimicrobial resistance, virulence, and prophage genes of six selected Brazilian strains of Salmonella Mbandaka using Whole Genome Sequencing (WGS). Multi-locus sequence typing revealed that the tested strains belong to Sequence Type 413 (ST413), which has been linked to recent multi-country salmonellosis outbreaks in Europe. A total of nine resistance genes were detected, and the most frequent ones were aac(6′)-Iaa, sul1, qacE, blaOXA-129, tet(B), and aadA1. A point mutation in ParC at the 57th position (threonine → serine) associated with quinolone resistance was present in all investigated genomes. A 112,960 bp IncHI2A plasmid was mapped in 4/6 strains. This plasmid harboured tetracycline (tetACDR) and mercury (mer) resistance genes, genes contributing to conjugative transfer, and genes involved in plasmid maintenance. Most strains (four/six) carried Salmonella genomic island 1 (SGI1). All S. Mbandaka genomes carried seven pathogenicity islands (SPIs) involved in intracellular survival and virulence: SPIs 1-5, 9, and C63PI. The virulence genes csgC, fimY, tcfA, sscA, (two/six), and ssaS (one/six) were absent in some of the genomes; conversely, fimA, prgH, and mgtC were present in all of them. Five Salmonella bacteriophage sequences (with homology to Escherichia phage phiV10, Enterobacteria phage Fels-2, Enterobacteria phage HK542, Enterobacteria phage ST64T, Salmonella phage SW9) were identified, with protein counts between 31 and 54, genome lengths of 24.7 bp and 47.7 bp, and average GC content of 51.25%. In the phylogenetic analysis, the genomes of strains isolated from poultry in Brazil clustered into well-supported clades with a heterogeneous distribution, primarily associated with strains isolated from humans and food. The phylogenetic relationship of Brazilian S. Mbandaka suggests the presence of strains with high epidemiological significance and the potential to be linked to foodborne outbreaks. Overall, our results show that isolated strains of S. Mbandaka are multidrug-resistant and encode a rather conserved virulence machinery, which is an epidemiological hallmark of Salmonella strains that have successfully disseminated both regionally and globally. [ABSTRACT FROM AUTHOR]

Simple Summary: In this study, the utilization of citrus oil (CO) as a natural antimicrobial solution to address bacterial diseases in poultry farming was examined, with a focus on pullorum disease and fowl typhoid in wooden chips employed as floor materials. With a decline in antibiotic use in poultry leading to a resurgence of bacterial infections like salmonellosis, CO has emerged as a promising alternative. The oil effectively inhibited the growth of various Salmonella serovars, particularly S. Gallinarum and S. Pullorum, demonstrating its potential to control these diseases. This study also found that CO, when applied to wooden chips in poultry house floors, prevents the development of Salmonella. Additionally, the research revealed that CO downregulates virulence genes in the bacteria, suggesting it could alter their harmful effects. Overall, this natural antimicrobial shows promise in preventing and managing salmonellosis in chicken production, offering a valuable alternative for addressing re-emerging diseases and promoting healthier poultry farming practices. This study investigates the potential role of Cold-pressed Valencia Terpeneless citrus oil (CO), as a natural antimicrobial, in controlling causative agents of pullorum disease and fowl typhoid in floor materials for poultry farming, specifically wooden chips. The study addresses the issues that have arisen as a result of the reduction in antibiotic use in poultry farming, which has resulted in the re-emergence of bacterial diseases including salmonellosis. CO efficiently inhibits the growth of pathogens including various serovars of Salmonella enterica (SE), including SE serovar Gallinarum (S. Gallinarum) and SE serovar Pullorum (S. Pullorum), in a dose-dependent manner. Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) of CO showed potential for controlling diverse S. Gallinarum and S. Pullorum isolates. Growth inhibition assays demonstrated that 0.4% (v/w) CO eliminated S. Pullorum and S. Gallinarum from 24 h onwards, also impacting poultry gut microbiota and probiotic strains. Floor material simulation, specifically wooden chips treated with 0.4% CO, confirmed CO's effectiveness in preventing S. Gallinarum and S. Pullorum growth on poultry house floors. This study also investigated the effect of CO on the expression of virulence genes in S. Gallinarum and S. Pullorum. Specifically, the study revealed that the application of CO resulted in a downregulation trend in virulence genes, including spiA, invA, spaN, sitC, and sifA, in both S. Pullorum and S. Gallinarum, implying that CO may alter the pathogenicity of these bacterial pathogens. Overall, this study reveals that CO has the potential to be used as a natural antimicrobial in the prevention and management of Salmonella-related infections in chicken production, offering a viable alternative to control these re-emerging diseases. [ABSTRACT FROM AUTHOR]

Simple Summary: Salmonella is one of the most important zoonotic pathogen agents, causing an estimated 93.8 million cases of gastroenteritis worldwide annually, with 155,000 deaths. Efforts to reduce transmission of Salmonella by food and other routes must be implemented on a global scale. Salmonellosis control strategies are based on two fundamental aspects: (a) the reduction of prevalence levels in animals and (b) protection against infection in humans. Thus, this review will be focused on Salmonella and its relationship between animals and public health (one health approach). The aim is to update the status of Salmonella in the world, with special reference to its implications on epidemiology and public health, food chain and risk assessment, antimicrobial resistance, and control strategies. We strongly believe that this review is an opportunity to collect significant and relevant information, using an integral approach, on Animal Health, Public Health, and the relationship between the two. Salmonellosis is globally recognized as one of the leading causes of acute human bacterial gastroenteritis resulting from the consumption of animal-derived products, particularly those derived from the poultry and pig industry. Salmonella spp. is generally associated with self-limiting gastrointestinal symptoms, lasting between 2 and 7 days, which can vary from mild to severe. The bacteria can also spread in the bloodstream, causing sepsis and requiring effective antimicrobial therapy; however, sepsis rarely occurs. Salmonellosis control strategies are based on two fundamental aspects: (a) the reduction of prevalence levels in animals by means of health, biosecurity, or food strategies and (b) protection against infection in humans. At the food chain level, the prevention of salmonellosis requires a comprehensive approach at farm, manufacturing, distribution, and consumer levels. Proper handling of food, avoiding cross-contamination, and thorough cooking can reduce the risk and ensure the safety of food. Efforts to reduce transmission of Salmonella by food and other routes must be implemented using a One Health approach. Therefore, in this review we provide an update on Salmonella, one of the main zoonotic pathogens, emphasizing its relationship with animal and public health. We carry out a review on different topics about Salmonella and salmonellosis, with a special emphasis on epidemiology and public health, microbial behavior along the food chain, predictive microbiology principles, antimicrobial resistance, and control strategies. [ABSTRACT FROM AUTHOR]

Salmonellosis is a disease transmitted by contaminated food and is one of the leading causes of infections worldwide, making the early detection of Salmonella of crucial importance for public health. However, current detection methods are laborious and time-consuming, thus impacting the entire food supply chain and leading to production losses and economic sanctions. To mitigate these issues, a number of different biosensors have been developed, including lateral flow assays (LFAs), which have emerged as valuable tools in pathogen detection due to their portability, ease of use, time efficiency, and cost effectiveness. The performance of LFAs has been considerably enhanced by the development of new nanomaterials over the years. In this review, we address the principles and formats of the assay and discuss future prospects and challenges with an emphasis on LFAs developed for the detection of different Salmonella serovars in food. [ABSTRACT FROM AUTHOR]

Salmonella is one of the leading causes of foodborne disease worldwide, usually related to contaminated poultry or poultry products, such as eggs. Since egg contamination with Salmonella depends on multiple factors that make it challenging to control, consumers' knowledge about food safety and the proper handling of eggs is crucial. The aims of the study were (1) to determine the prevalence of Salmonella in eggs from conventional and alternative production systems, (2) to characterize the Salmonella isolates according to phenotypic-genotypic and antimicrobial-resistant traits, and (3) to understand how consumers manage the hazards related to egg contamination in the household. A total of 426 egg samples were analyzed (conventional systems = 240; alternative systems = 186). Culture-based and molecular microbiological methods were used to identify Salmonella and bioinformatics analysis of whole genome sequences was used to determine the serotype and antimicrobial-resistant genes. Salmonella enterica serotype Enteritidis was detected only in eggs from alternative systems (1.1%, 2/186). Isolates showed resistance to nalidixic acid (100%, 2/2), and the aac(6′)-Iaa gene and a mutation in the gyrA gene were identified in both isolates. Overall, consumers demonstrated knowledge regarding food safety; however, many still engage in practices that pose a risk of acquiring foodborne illnesses. [ABSTRACT FROM AUTHOR]

Simple Summary: Salmonellosis is the second most reported gastrointestinal disorder in the European Union, resulting from the consumption of Salmonella-contaminated foods. Chickens are considered reservoirs of this pathogen among food-producing animals, for which hygienic and sanitary measures mitigate the risk to humans through the food chain. However, data about the presence of this pathogen in autochthonous Portuguese chickens or their by-products is scarce. In this context, the aim of this study was to conduct a preliminary investigation on the occurrence of Salmonella spp. in autochthonous Portuguese laying hens raised in a semi-extensive system for small-scale production. The screening revealed an absence of Salmonella spp. in all cloaca, eggshell, and litter material samples collected (n = 279) from the 31 selected flocks. Considering these results and the fact that Salmonella is still the leading cause of food-borne outbreaks, the risk posed by Portuguese autochthonous chicken breeds produced through alternative and extensive farming methods can be considered low. However, this risk should not be neglected and needs to be further investigated, using a larger sample size, to validate this trend. The sustainability of agroecological systems, biodiversity protection, animal welfare, and consumer demand for higher quality products from alternative and extensive farming methods have reinforced interest in local breeds that are well adapted to low-input environments. However, food safety needs to be safeguarded to reinforce consumer confidence. The aim of this study was to conduct a preliminary investigation on the occurrence of Salmonella spp. in eggshells, hen's cloaca, and litter materials from autochthonous Portuguese laying hens raised in a semi-extensive system for small-scale production. A total of 279 samples from 31 flocks belonging to 12 farms were obtained, with 63 samples from the "Preta Lusitânica" breed, and 72 samples each from the remaining autochthonous breeds, namely, "Branca", "Amarela", and "Pedrês Portuguesa". None (0%) of the samples analyzed were positive for Salmonella spp. To the best of our knowledge, these are the first results of Salmonella evaluation from hen's cloaca, eggshells, and litter materials in autochthonous Portuguese chickens, suggesting that a semi-extensive production system can contribute to better food security and a lower risk to public health and the environment. [ABSTRACT FROM AUTHOR]

The objective of this retrospective study was to evaluate the clinical significance of fecal quantitative real-time polymerase chain reaction (qPCR) Salmonella results when taking the cycle threshold values (Ct) into account. The study included 120 Salmonella qPCR-positive fecal samples obtained from 88 hospitalized horses over a 2-year period. The mean Ct of the qPCR test was evaluated in regard to (1) clinical outcome and (2) systemic inflammatory response syndrome (SIRS) status (no SIRS, moderate SIRS, or severe SIRS) of the sampled horses. An ROC analysis was performed to establish the optimal cut-off Ct values associated with severe SIRS. The mean ± SD Ct value was significantly lower in samples (1) from horses with a fatal issue (27.87 ± 5.15 cycles) than in surviving horses (31.75 ± 3.60 cycles), and (2) from horses with severe SIRS (27.87 ± 2.78 cycles) than from horses with no (32.51 ± 3.59 cycles) or moderate (31.54 ± 3.02 cycles) SIRS. In the ROC analysis, the optimal cut-off value of Ct associated with a severe SIRS was 30.40 cycles, with an AUC value of 0.84 [95% confidence interval 0.76–0.91] and an OR of 0.64 [0.51–0.79]. Results suggest that including the Ct value in the interpretation of fecal qPCR results could improve the diagnostic value of this test for clinical salmonellosis in horses. [ABSTRACT FROM AUTHOR]

Due to irrational antibiotic stewardship, an increase in the incidence of multidrug resistance of bacteria has been observed recently. Therefore, the search for new therapeutic methods for pathogen infection treatment seems to be necessary. One of the possibilities is the utilization of bacteriophages (phages)—the natural enemies of bacteria. Thus, this study is aimed at the genomic and functional characterization of two newly isolated phages targeting MDR Salmonella enterica strains and their efficacy in salmonellosis biocontrol in raw carrot–apple juice. The Salmonella phage vB_Sen-IAFB3829 (Salmonella phage strain KKP 3829) and Salmonella phage vB_Sen-IAFB3830 (Salmonella phage strain KKP 3830) were isolated against S. I (6,8:l,-:1,7) strain KKP 1762 and S. Typhimurium strain KKP 3080 host strains, respectively. Based on the transmission electron microscopy (TEM) and whole-genome sequencing (WGS) analyses, the viruses were identified as members of tailed bacteriophages from the Caudoviricetes class. Genome sequencing revealed that these phages have linear double-stranded DNA and sizes of 58,992 bp (vB_Sen-IAFB3829) and 50,514 bp (vB_Sen-IAFB3830). Phages retained their activity in a wide range of temperatures (from −20 °C to 60 °C) and active acidity values (pH from 3 to 11). The exposure of phages to UV radiation significantly decreased their activity in proportion to the exposure time. The application of phages to the food matrices significantly reduced the level of Salmonella contamination compared to the control. Genome analysis showed that both phages do not encode virulence or toxin genes and can be classified as virulent bacteriophages. Virulent characteristics and no possible pathogen factors make examined phages feasible to be potential candidates for food biocontrol. [ABSTRACT FROM AUTHOR]

Salmonella enterica is the principal causative agent of salmonellosis, a threat to human health. Because of its high antimicrobial resistance potential, Salmonella enterica has become worrisome, mostly in developing countries where hygiene and antimicrobial usage are defective. This study aimed to determine the epidemiology of the intestinal carriage of Extended Spectrum β-Lactamase producing Salmonella enterica from chickens and poultry farmers in Dschang, a town in the western region of Cameroon. A total of 416 chickens and 72 farmers were sampled between May and October 2020; and Salmonella enterica were isolated and subjected to extended spectrum β-lactamase screening. Logistic regression was used to test for statistical associations using a p-value of ≤0.05. Results from this study revealed that the prevalence of the intestinal carriage of Salmonella enterica for chickens and farmers were 55.77% [51.00; 60.54] and 22.22% [12.62; 31.82], respectively. Meanwhile, the intestinal carriage of Extended Spectrum β-Lactamase producing Salmonella enterica was 23.08% [13.76; 32.40] and 5.55% [0.26; 10.84] from chickens and poultry farmers, respectively. The risk factor for this carriage was revealed to be lack of knowledge by actors in livestock industries of antibiotic resistance. Chickens, just like poultry farmers, represent the starting point of community salmonellosis, which is difficult to cure; therefore, sensitization of breeders is an effective tool for the mitigation of this burden. [ABSTRACT FROM AUTHOR]

Bacterial vaccines have become a crucial tool in combating antimicrobial resistance (AMR) in poultry. The overuse and misuse of antibiotics in poultry farming have led to the development of AMR, which is a growing public health concern. Bacterial vaccines are alternative methods for controlling bacterial diseases in poultry, reducing the need for antibiotics and improving animal welfare. These vaccines come in different forms including live attenuated, killed, and recombinant vaccines, and they work by stimulating the immune system to produce a specific response to the target bacteria. There are many advantages to using bacterial vaccines in poultry, including reduced use of antibiotics, improved animal welfare, and increased profitability. However, there are also limitations such as vaccine efficacy and availability. The use of bacterial vaccines in poultry is regulated by various governmental bodies and there are economic considerations to be taken into account, including costs and return on investment. The future prospects for bacterial vaccines in poultry are promising, with advancements in genetic engineering and vaccine formulation, and they have the potential to improve the sustainability of the poultry industry. In conclusion, bacterial vaccines are essential in combating AMR in poultry and represent a crucial step towards a more sustainable and responsible approach to poultry farming. [ABSTRACT FROM AUTHOR]

Simple Summary: The poultry sector is an essential component of agriculture that has grown unusually over the past few decades. Salmonella is thought to live naturally in chickens and causes salmonellosis in humans. Many plant extracts, mainly essential oils, have had their active ingredients studied. Salmonella in chicken is resistant to the antimicrobial effects of the aromatic oil eugenol, which is present mainly in cinnamon and clove. Therefore, eugenol supplementation also improves gut health, thereby increasing overall well-being. Here, we reviewed the rising rates of salmonellosis worldwide and the factors contributing to its prevalence. Then, we suggested using eugenol as a natural feed supplement for reducing Salmonella in chicken. The poultry sector is an essential component of agriculture that has experienced unprecedented growth during the last few decades. It is especially true for the United States, where the average intake of chicken meat increased from 10 pounds (4.5 kg) per person in 1940 to 65.2 pounds (29.6 kg) per person in 2018, while the country produced 113 billion eggs in 2019 alone. Besides providing nutrition and contributing significantly to the economy, chicken is also a natural reservoir of Salmonella, which is responsible for salmonellosis in humans, one of the significant foodborne illnesses around the globe. The increasing use of chicken manure and antibiotics increases the spread of Salmonella and selects for multi-drug resistant strains. Various plant extracts, primarily essential oils, have been investigated for their antimicrobial activities. The multiple ways through which these plant-derived compounds exert their antimicrobial effects make the development of resistance against them unlikely. Eugenol, an aromatic oil primarily found in clove and cinnamon, has shown antimicrobial activities against various pathogenic bacteria. A few reports have also highlighted the anti-Salmonella effects of eugenol in chicken, especially in reducing the colonization by Salmonella Enteritidis and Salmonella Typhimurium, the primary Salmonella species responsible for human salmonellosis. Besides limiting Salmonella infection in chicken, the supplementation of eugenol also significantly improves intestinal health, improving overall well-being. In this review, we highlight the rising incidences of salmonellosis worldwide and the factors increasing its prevalence. We then propose the usage of eugenol as a natural feed supplement for containing Salmonella in chicken. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

(1) Background: Foodborne illness from Salmonella enterica subspecies I is most associated with approximately 32 out of 1600 serotypes. While whole genome sequencing and other nucleic acid-based methods are preferred for serotyping, they require expertise in bioinformatics and often submission to an external agency. Intergenic Sequence Ribotyping (ISR) assigns serotype to Salmonella in coordination with information freely available at the National Center for Biotechnology Information. ISR requires updating because it was developed from 26 genomes while there are now currently 1804 genomes and 1685 plasmids. (2) Methods: Serotypes available for sequencing were analyzed by ISR to confirm primer efficacy and to identify any issues in application. Differences between the 2012 and 2022 ISR database were tabulated, nomenclature edited, and instances of multiple serotypes aligning to a single ISR were examined. (3) Results: The 2022 ISR database has 268 sequences and 40 of these were assigned new NCBI accession numbers that were not previously available. Extending boundaries of sequences resolved hdfR cross-alignment and reduced multiplicity of alignment for 37 ISRs. Comparison of gene cyaA sequences and some cell surface epitopes provided evidence that homologous recombination was potentially impacting results for this subset. There were 99 sequences that still had no match with an NCBI submission. (4) The 2022 ISR database is available for use as a serotype screening method for Salmonella enterica subspecies I. Finding that 36.9% of the sequences in the ISR database still have no match within the NCBI Salmonella enterica database suggests that there is more genomic heterogeneity yet to characterize. [ABSTRACT FROM AUTHOR]

Simple Summary: Salmonella contamination in the poultry supply chain is a global public concern and can lead to a serious foodborne illness; thus, effective control measures are needed. Here, we focused on the application of phage treatment to control Salmonella during the pre-harvest step of poultry meat production. Salmonella reduction was monitored in broilers on a commercial farm. Phage treatment has been proposed as a potential alternative biocontrol agent for agricultural purposes due to its specificity and safety, whereby it will only target bacterial hosts without harmful effects on human and animal health. Phages not only provide benefits for reducing the number of pathogens, but they are also easy to apply or deliver to a wide range of animals. In this study, phages and a phage cocktail were developed to provide an effective method for reducing Salmonella colonization in the gastrointestinal tract of broilers to improve food safety from farm to fork. Salmonella contamination in poultry meat products can lead to serious foodborne illness and economic loss from product recalls. It is crucial to control Salmonella contamination in poultry from farm to fork. Bacteriophages (phages) are viruses of bacteria that offer several advantages, especially their specificity to target bacteria. In our study, three Salmonella phages (vB_SenS_KP001, vB_SenS_KP005, and vB_SenS_WP110) recovered from a broiler farm and wastewater treatment stations showed high lysis ability ranging from 85.7 to 96.4% on over 56 serovars of Salmonella derived from several sources, including livestock and a broiler farm environment. A three-phage cocktail reduced S. Enteritidis and S. Typhimurium, in vitro by 3.9 ± 0.0 and 3.9 ± 0.2 log units at a multiplicity of infection (MOI) of 103 and 3.8 ± 0.4 and 4.1 ± 0.2 log units at MOI of 104 after 6 h post-phage treatment. A developed phage cocktail did not cause phage resistance in Salmonella during phage treatments for three passages. Phages could survive under simulated chicken gastrointestinal conditions in the presence of gastric acid for 2 h (100.0 ± 0.0% survivability), bile salt for 1 h (98.1 ± 1.0% survivability), and intestinal fluid for 4 h (100 ± 0.0% survivability). Each phage was in the phage cocktail at a concentration of up to 9.0 log PFU/mL. These did not cause any cytotoxicity to human fibroblast cells or Caco-2 cells as indicated by the percent of cell viability, which remained nearly 100% as compared with the control during 72 h of co-culture. The phage cocktail was given to broilers raised in commercial conditions at a 9 log PFU/dose for five doses, while naturally occurring Salmonella cells colonized in the gastrointestinal tract of broilers were significantly reduced as suggested by a considerably lower Salmonella prevalence from over 70 to 0% prevalence after four days of phage treatment. Our findings suggest that a phage cocktail is an effective biocontrol agent to reduce Salmonella present in the guts of broilers, which can be applied to improve food safety in broiler production. [ABSTRACT FROM AUTHOR]

Simple Summary: Salmonellosis is an infectious bacterial disease, which causes moderate to severe gastrointestinal manifestations or severe syndromes, including septicemia and death. The presence of Salmonella spp. in captive exotic felids is generally asymptomatic in adults that may act as environmental carriers and shedders of the bacterium. This case report describes the occurrence of fatal septicemia with meningoencephalitis in a Panthera tigris cub caused by Salmonella Enteritidis. The fragility of the perinatal period (e.g., inadequate management and poor parental care) and a possible immunocompromised state of the infected cub may have favored the systemic spread of the infection and the colonization of the central nervous system. This case highlights the importance of thoroughly investigating the causes of perinatal mortality in captive felids, both for animal health protection and for potential zoonotic implications. A 15-day-old, female, captive Panthera tigris cub was hospitalized after developing severe hyperthermia, depression, and lack of appetite. The clinical condition rapidly worsened, and the tiger cub died in 72 h after the onset of neurological symptoms, septic shock, and multiple organ dysfunction syndrome. The postmortem main gross findings consisted of a severe and diffuse bilateral fibrino-suppurative meningoencephalitis and ventriculitis, mild fibrinous and sero-hemorrhagic polyserositis and cystitis, severe pulmonary edema, and hemorrhages. Microscopically, the meninges, ependyma, and choroid plexuses were diffusely expanded by abundant infiltration of neutrophils and macrophages, with multifocal fibrinous exudation. Histiocytic interstitial pneumonia, fibrinous and neutrophilic polyserositis, and pyelocystitis were also observed. Vascular thrombosis with multifocal vasculitis and vascular necrosis were frequently observed. Aerobic and anaerobic cultures performed on the brain, lungs, intestine, kidneys, and in pericardial effusion reported the presence of Salmonella enterica subsp. enterica serovar Enteritidis. Environmental and nutritional contamination were identified as putative sources of infections. To the best of the authors' knowledge, this is the first report of Salmonella Enteritidis septicemia with meningoencephalitis in a tiger cub, which highlights the need to further investigate the cause of acute perinatal death to reduce the risk of infectious disease outbreaks. [ABSTRACT FROM AUTHOR]

A zoonosis is an infectious disease that has jumped from a non-human animal to humans. Some zoonoses are very common in the Mediterranean area and endemic in specific regions, so they represent an important problem for public health. Human Immunodeficiency Virus (HIV) is a virus that has originated as a zoonosis and is now diffused globally, with the most significant numbers of infected people among the infectious diseases. Since the introduction of antiretroviral therapy (ART), the history for people living with HIV (PLWH) has changed drastically, and many diseases are now no different in epidemiology and prognosis as they are in not-HIV-infected people. Still, the underlying inflammatory state that is correlated with HIV and other alterations related to the infection itself can be a risk factor when infected with other bacteria, parasites or viruses. We reviewed the literature for infection by the most common Mediterranean zoonoses, such as Campylobacter, Salmonella, Brucella, Rickettsia, Borrelia, Listeria and Echinococcus, and a possible correlation with HIV. We included Monkeypox, since the outbreak of cases is becoming a concern lately. We found that HIV may be related with alterations of the microbiome, as for campylobacteriosis, and that there are some zoonoses with a significant prevalence in PLWH, as for salmonellosis. [ABSTRACT FROM AUTHOR]

Endocarditis is an extremely rare complication of Salmonellosis with an incidence of 0.2–0.4%. It is a destructive and invasive infection that follows a highly complicated course and carries a high mortality rate that exceeds 45%. Multiple predisposing factors for Salmonella endocarditis have been described in the literature, including human immunodeficiency virus infection, congenital heart diseases, and the presence of a prosthetic valve. Herein, we report a case of Salmonella prosthetic valve endocarditis complicated by splenic infarction and aortic pseudoaneurysm presenting as a month-long history of fluctuating fever, chills, and rigors, accompanied by occasional cough and shortness of breath in a 55-year-old female with aortic and mitral valves replacement and multiple comorbidities. She was diagnosed by multiple radiographic studies and successfully treated with the Commando procedure and a long course of IV antibiotics. [ABSTRACT FROM AUTHOR]

Salmonellosis caused by Salmonella sp. has long been reported all over the world. Despite the availability of various diagnostic methods, easy and effective detection systems are still required. This report describes a dialysis membrane electrode interface disc with immobilized specific antibodies to capture antigenic Salmonella cells. The interaction of a specific Salmonella antigen with a mouse anti-Salmonella monoclonal antibody complexed to rabbit anti-mouse secondary antibody conjugated with HRP and the substrate o-aminophenol resulted in a response signal output current measured using two electrode systems (cadmium reference electrode and glassy carbon working electrode) and an agilent HP34401A 6.5 digital multimeter without a potentiostat or applied potential input. A maximum response signal output current was recorded for various concentrations of Salmonella viz., 3, 30, 300, 3000, 30,000 and 300,000 cells. The biosensor has a detection limit of three cells, which is very sensitive when compared with other detection sensors. Little non-specific response was observed using Streptococcus, Vibrio, and Pseudomonas sp. The maximum response signal output current for a dialysis membrane electrode interface disc was greater than that for gelatin, collagen, and agarose. The device and technique have a range of biological applications. This novel detection system has great potential for future development and application in surveillance for microbial pathogens. [ABSTRACT FROM AUTHOR]

This review revisits previous concepts on biological phenomenon contributing to the success of the Salmonella enterica subspecies I as a pathogen and expands upon them to include progress in epidemiology based on whole genome sequencing (WGS). Discussion goes beyond epidemiological uses of WGS to consider how phenotype, which is the biological character of an organism, can be correlated with its genotype to develop a knowledge of the interactome. Deciphering genome interactions with proteins, the impact of metabolic flux, epigenetic modifications, and other complex biochemical processes will lead to new therapeutics, control measures, environmental remediations, and improved design of vaccines. [ABSTRACT FROM AUTHOR]

Globally, there has been an increase in squamates (particularly lizards and snakes) being kept as pets. Additionally, urban spread has resulted in greater human encroachment and interaction with the natural habitat of wild squamates. A potential consequence of increasing human interaction with squamates is the increased potential for disease transfer. This review collates the literature describing clinical salmonellosis cases that were definitively linked to a squamate through testing of the animal and population-based studies which investigate the risk of salmonellosis linked to pet squamates. It was demonstrated that although squamate-acquired salmonellosis accounted for a small percentage of total cases, children under five were at greatest risk, with the clinical manifestations tending to be more severe. In many cases, it was noted that the patient was unaware of the risks associated with keeping squamates and did not practice proper hand hygiene after handling the animals or cleaning cages. This highlights the need for more education focused on informing the general public of ways to reduce the risk of salmonellosis from pet squamates. There is also the need for future research into the role of wild squamates in the spread of human salmonellosis, both directly and indirectly through cross contamination. [ABSTRACT FROM AUTHOR]

Egypt has a unique geographical location connecting the three old-world continents Africa, Asia and Europe. It is the country with the highest population density in the Middle East, Northern Africa and the Mediterranean basin. This review summarizes the prevalence, reservoirs, sources of human infection and control regimes of common bacterial, parasitic and viral zoonoses in animals and humans in Egypt. There is a gap of knowledge conerning the epidemiology of zoonotic diseases at the human-animal interface in different localities in Egypt. Some zoonotic agents are "exotic" for Egypt (e.g., MERS-CoV and Crimean-Congo hemorrhagic fever virus), others are endemic (e.g., Brucellosis, Schistosomiasis and Avian influenza). Transboundary transmission of emerging pathogens from and to Egypt occurred via different routes, mainly importation/exportation of apparently healthy animals or migratory birds. Control of the infectious agents and multidrug resistant bacteria in the veterinary sector is on the frontline for infection control in humans. The implementation of control programs significantly decreased the prevalence of some zoonoses, such as schistosomiasis and fascioliasis, in some localities within the country. Sustainable awareness, education and training targeting groups at high risk (veterinarians, farmers, abattoir workers, nurses, etc.) are important to lessen the burden of zoonotic diseases among Egyptians. There is an urgent need for collaborative surveillance and intervention plans for the control of these diseases in Egypt. [ABSTRACT FROM AUTHOR]

Non-typhoidal salmonellosis (NTS) is one of the most common foodborne diseases worldwide. In this study, we aimed to analyze trends in the epidemiology of NTS in the last decade in Israel. Laboratory-confirmed cases of NTS at eight sentinel laboratories were reported to the Israel Sentinel Laboratory-Based Surveillance Network, integrated with the serotype identification performed at the Salmonella National Reference Laboratory of the Ministry of Health. The decrease in NTS incidence since 1999 continued between 2010 and 2014 (16.1 per 100,000 in 2014) and was interrupted by a rise between 2015 and 2017 (39.1 per 100,000 in 2017) associated with outbreaks of Salmonella Enteritidis. The incidence of NTS dropped again thereafter (21.4 per 100,000 in 2021). The 0-4 age group was the most affected by NTS (55.5% of the cases) throughout the surveillance period. The age-adjusted incidence rates were consistently high in the summer months (June-September) and low in the winter months (December-February). The overall decrease in the incidence of NTS in Israel since 1999 was temporarily interrupted in the last decade by country-wide outbreaks involving emerging or re-emerging Salmonella serotypes. Control measures should be enhanced for all risk points of food chain transmission of Salmonella spp. to further reduce the NTS morbidity in Israel.

Salmonella enterica is one of the most dangerous foodborne pathogens listed by the World Health Organization. In this study, whole-duck samples were collected at wet markets in five districts in Hanoi, Vietnam, in October 2019 to assess their Salmonella infection rates and evaluate the susceptibility of the isolated strains to antibiotics currently used in the prophylaxis and treatment of Salmonella infection. Based on the antibiotic resistance profiles, eight multidrug resistance strains were whole-genome-sequenced, and their antibiotic resistance genes, genotypes, multi-locus sequence-based typing (MLST), virulence factors, and plasmids were analyzed. The results of the antibiotic susceptibility test indicate that phenotypic resistance to tetracycline and cefazolin was the most common (82.4%, 28/34 samples). However, all isolates were susceptible to cefoxitin and meropenem. Among the eight sequenced strains, we identified 43 genes associated with resistance to multiple classes of antibiotics such as aminoglycoside, beta-lactam, chloramphenicol, lincosamide, quinolone, and tetracycline. Notably, all strains carried the bla CTX-M-55 gene, which confers resistance to third-generation antibiotics including cefotaxime, cefoperazone, ceftizoxime, and ceftazidime, as well as resistance genes of other broad-spectrum antibiotics used in clinical treatment such as gentamicin, tetracycline, chloramphenicol, and ampicillin. Forty-three different antibiotic resistance genes were predicted to be present in the isolated Salmonella strains' genomes. In addition, three plasmids were predicted in two strains, 43&#95;S11 and 60&#95;S17. The sequenced genomes also indicated that all strains carried SPI-1, SPI-2, and SPI-3. These SPIs are composed of antimicrobial resistance gene clusters and thus represent a potential threat to public health management. Taken together, this study highlights the extent of multidrug-resistant Salmonella contamination in duck meat in Vietnam.

Salmonella spp. continues to figure prominently in world epidemiological registries as one of the leading causes of bacterial foodborne disease. We characterised 43 Brazilian lineages of Salmonella Typhimurium (ST) strains, characterized drug resistance patterns, tested copper (II) complex as control options, and proposed effective antimicrobial measures. The minimum inhibitory concentration was evaluated for seven antimicrobials, isolated and combined with the copper (II) complex [Cu(4-FH)(phen)(ClO4)2] (4-FH = 4-fluorophenoxyacetic acid hydrazide and phen = 1,10-phenanthroline), known as DRI-12, in planktonic and sessile ST. In parallel, 42 resistance genes were screened (PCR/microarray). All strains were multidrug resistant (MDR). Resistance to carbapenems and polymyxins (86 and 88%, respectively) have drawn attention to the emergence of the problem in Brazil, and resistance is observed also to CIP and CFT (42 and 67%, respectively), the drugs of choice in treatment. Resistance to beta-lactams was associated with the genes blaTEM/blaCTX-M in 39% of the strains. Lower concentrations of DRI-12 (62.7 mg/L, or 100 μM) controlled planktonic and sessile ST in relation to AMP/SUL/TET and AMP/SUL/TET/COL, respectively. The synergistic effect provided by DRI-12 was significant for COL/CFT and COL/AMP in planktonic and sessile ST, respectively, and represents promising alternatives for the control of MDR ST. [ABSTRACT FROM AUTHOR]

Salmonella Enteritidis is a major foodborne pathogen worldwide. In this study, a total of 276 S. enteritidis isolates, collected between 2016 and 2017 from human, food and farm/slaughterhouse samples, were studied to enhance the understanding of the epidemiology of human salmonellosis in Singapore. Results showed all 276 isolates belonged either to ST1925 (70.3%) or ST11 (29.7%), with ST11 being significantly more frequent in extra-intestinal isolates and chicken isolates. Food isolates, most of which were from poultry, showed the highest prevalence of resistance (33-37%) against beta-lactams or beta-lactams/beta-lactamase inhibitor combination (ampicillin, piperacillin and ampicillin/sulbactam). The analysis showed the detection of genes associated with resistance to aminoglycoside genes (99.6%), tetracycline (55.1%), and beta-lactams (14.9%) of all isolates. Nine types of plasmids were found in 266 isolates; the most common incompatibility group profiles were IncFIB(S)-IncFII(S)-IncX1 (72.2%) and IncFIB(S)-IncFII(S) (15.8%). Most plasmid harbouring isolates from chicken (63.6%, 14/22) and from human (73.8%, 175/237) shared the same plasmid profile (IncFIB(S)-IncFII(S)-IncX1). SNP analysis showed clustering of several isolates from poultry food products and human isolates, suggesting phylogenetic relatedness among these isolates. Lastly, this study provides important epidemiological insights on the application of phenotypic and next-generation sequencing (NGS) tools for improved food safety and public health surveillance and outbreak investigation of S. enteritidis .

Background: There are few studies on sex differences in the incidence rates (IR) for salmonellosis over several countries by age and time period. The purpose of this study was to explore the extent and consistency of the sex and age-specific differences. Methods: We analyzed national data from eight countries between 1994 and 2016. We computed country-specific male to female incidence rate ratios (IRRs) for each age group and pooled the data using meta-analytic methods. Variations of the IRRs by age, country and time period were evaluated using meta-regression. Results: The pooled male to female incidence RRs for ages 0–1, 1–4, 5–9 and 10–14, were 1.04 (1.02–1.06), 1.02 (1.01–1.03), 1.07 (1.05–1.08) and 1.28 (1.23–1.33), respectively. For the ages 15–44 and 45–64, the incidence rates were significantly higher in females. Meta-regression analyses indicate that age groups contributed most of the variation in the male to female IRRs. Conclusions: We suggest that genetic and hormonal factors and interactions between hormones and gut microbiota could contribute to the sex differences observed in young children. These findings should provide clues about the mechanisms of the infection, and should be useful in targeting treatments and development of vaccines. Highlights: (1) This manuscript provides consistent estimates of the excess salmonellosis incidence rates in male children up to age 15, which suggests an impact of sex hormones or genetic differences. (2) Our findings should promote the further investigations on sex-related determinants of infectious diseases. [ABSTRACT FROM AUTHOR]

The Salmonella Enterica subsp. Enterica serovar Enteritidis is one of main serovars isolated from human patients with food poisoning and poultry without clinical signs. Consumption of poultry products contaminated with Salmonella Enteritidis is a common source of human salmonellosis; 82 Salmonella spp. were isolated from 291 samples of retail chicken meat, 201 one-day-old chicks, 30 internal organs of chickens, 156 chicken eggs, 100 duck eggs, 38 straw bedding samples, 18 samples of retail duck meat, and 19 swab samples from slaughterhouses in 2019 and 2020. An antibiotic susceptibility test was performed for all isolates, revealing 33 multidrug-resistant (MDR) strains. The whole genome of 33 MDR strains isolated in 2019 and 2020 and 10 strains isolated in 2011, 2012, and 2017 was sequenced using the MinION sequencing protocol. Within these 43 samples, 5 serovars were identified: S. Enteritidis, S. Agona, S. Virchow, S. Albany, and S. Bareilly. The most common serovar was S. Enteritidis (26/43), which showed the highest resistance to ampicillin (100%), followed by nalidixic acid (90%) and colistin (83%). Core genome multilocus sequence typing analysis showed that the S. Enteritidis strains isolated from different sources and in different years were clustered together. In addition, the S. Enteritidis strains isolated since 2011 consistently harbored the same antibiotic resistance patterns. [ABSTRACT FROM AUTHOR]

In the absence of consistent national molecular typing data to enhance the surveillance of Salmonella Enteritidis, it was considered useful to collect baseline information on the genetic diversity and antibiotic susceptibility of strains isolated in Romania between January 2016 and April 2020 and compare them to strains described in major international outbreaks of the same period. A collection of 245 clinical isolates were genotyped by a standardised multiple-locus variable-number of tandem repeats analysis (MLVA) 5-loci protocol and screened for antimicrobial resistance against 15 compounds. Twenty strains were further subjected to whole genome sequencing (WGS) and compared to epidemiologically relevant high-throughput sequencing data available in European databases. Twenty-seven MLVA genotypes were identified, of which three, commonly reported in Europe between 2016–2020, covered 72% of the collection. Antibiotic resistance was detected in 30% of the strains, with resistance to nalidixic acid and ciprofloxacin as the most common phenotype, and also associated with two prevalent MLVA clones. WGS-derived multilocus sequence typing (MLST) revealed a single sequence type (ST11) further resolved into 10 core-genome MLST complex types. The minimum spanning tree constructed from the cgMLST data clustered Romanian and international strains, which shared more than 95% of the core genes, revealing links with a contemporaneous multi-country outbreak. This study could be regarded as a forerunner to the advent of using this integrative approach in the public health practice at a national level and thus contribute to the concerted actions at a European level to stop outbreaks. [ABSTRACT FROM AUTHOR]

Foodborne disease caused by Salmonella is an important public health concern worldwide. Animal-based food, especially poultry meat, is the main source of human salmonellosis. The objective of this study was to evaluate the prevalence and epidemiology of Salmonella contamination in raw poultry meat commercialized in China. Following the principle of systematic review, 98 sets of prevalence data were extracted from 74 publications conducted in 21 Chinese provincial regions. The random-effect model was constructed for subgrouping analysis by meat category, preservation type, and geographical location. The prevalence levels differed from high to low among raw poultry meat, including chicken, 26.4% (95% CI: 22.4–30.8%); pigeon, 22.6% (95% CI: 18.2–27.8%); duck, 10.1% (95% CI: 5.3–18.2%); and other poultry meat, 15.4% (95% CI: 12.0–19.5%). Prevalence data on the preservation type revealed that chilled poultry meat might be more likely to experience cross-contamination than non-chilled poultry meat in China. The distribution map of Salmonella for raw poultry meat showed that a higher prevalence level was found in the Shaanxi, Henan, Sichuan, and Beijing regions. All subgroups possessed high amounts of heterogeneity (I2 > 75%). The scientific data regarding the differences in prevalence levels between meat category, preservation method, and geographical region sources might be useful to improve specific interventions to effectively control the incidence of Salmonella in poultry meat. [ABSTRACT FROM AUTHOR]

Since the occurrence of swine salmonellosis has increased over time and control strategies other than biosecurity are highly recommended, the present study aimed to evaluate the efficacy of vaccination with Salmonella Choleraesuis and Salmonella Typhimurium bacterins in pigs. Two experimental groups were formed: G1, animals immunized with two doses of a commercial vaccine (n = 20); G2, control group (n = 20). After vaccination, all pigs were orally challenged (D0) with 108 CFU of Salmonella Typhimurium and evaluated for 40 days. Every 10 days after D0, five piglets from each experimental group were euthanized and submitted to the necroscopic examination, when organ samples were collected. Blood samples and rectal swabs were collected before the first dose of the vaccine (D−42), before the second dose (D−21), before the challenge (D0), and thereafter, every three days until D39. Blood count, serum IgG measurement by ELISA, and the excretion of Salmonella Typhimurium in feces were evaluated. While the results from blood count and serum IgG concentration did not differ, the detection and excretion of Salmonella between G1 and G2 differed (p < 0.05). Therefore, it was observed that this vaccine partially protected the animals against experimental infection with Salmonella Typhimurium, reducing the excretion of bacteria in feces. [ABSTRACT FROM AUTHOR]

Salmonella Typhimurium (STm) represents the most prevalent cause of invasive non-typhoidal Salmonella (iNTS) disease, and currently no licensed vaccine is available. In this work we characterized the long-term anti-bacterial immunity elicited by a STm vaccine based on Generalized Modules of Membrane Antigens (GMMA) delivering O:4,5 antigen, using a murine model of systemic infection. Subcutaneous immunization of mice with STmGMMA/Alhydrogel elicited rapid, high, and persistent antigen-specific serum IgG and IgM responses. The serum was bactericidal in vitro. O:4,5-specific IgG were also detected in fecal samples after immunization and positively correlated with IgG observed in intestinal washes. Long-lived plasma cells and O:4,5-specific memory B cells were detected in spleen and bone marrow. After systemic STm challenge, a significant reduction of bacterial load in blood, spleen, and liver, as well as a reduction of circulating neutrophils and G-CSF glycoprotein was observed in STmGMMA/Alhydrogel immunized mice compared to untreated animals. Taken together, these data support the development of a GMMA-based vaccine for prevention of iNTS disease. [ABSTRACT FROM AUTHOR]