Foodborne Bacterial Infections Research Articles

Polysaccharide- and protein-based edible films combined with microwave technology for meat preservation

To reduce food-borne bacterial infection caused by food spoilage, developing highly efficient food packing film is still an urgent need for food preservation. Herein, microwave-assisted antibacterial nanocomposite films CaO2@PVP/EA/CMC-Na (CP/EC) were synthesized using waste eggshell as precursor, egg albumen (EA) and sodium carboxymethylcellulose (CMCNa) as matrix by casting method. The size of CaO2@PVP (CP) nanoparticles with monodisperse spherical structures was 100–240 nm. When microwave and CP nanoparticles (0.05 mg/mL) were treated for 5 min, the mortality of E. coli and S. aureus could reach >97 %. Under microwave irradiation (6 min), the bactericidal rate of 2.5 % CP/EC film against E. coli and S. aureus reached 98.6 % and 97.2 %, respectively. After adding CP nanoparticles, the highest tensile strength (TS) and elongation at break (EB) of CP/EC film reached 19.59 MPa and 583.43 %, respectively. At 18 °C, the proliferation of bacterial colonies on meat can be significantly inhibited by 2.5 % CP/EC film. Detailed characterization showed that the excellent meat preservation activity was due to the synergistic effect of dynamic effect generated by ROS and thermal effect of microwave. This study provides a promising approach for the packaging application of polysaccharide- and protein-based biomass nanocomposite antibacterial edible films.

Detection of Campylobacter jejuni based on CRISPR/Cas12a with novel target yclQ obtained by pan-genome analysis

Campylobacter jejuni (C. jejuni) is one of the most common causes of bacterial gastrointestinal foodborne infections worldwide. Conventional detection methods based on bacterial culture are time-consuming, therefore, rapid detection methods are urgently needed to be developed. The objective of this study was to screen a novel species-specific target and to develop a rapid and accurate method for the detection of C. jejuni in food. Through pan-genome analysis of 298 Campylobacter whole-genome sequence data, a new species-specific target yclQ was screened. The yclQ gene was verified through PCR to be unique to C. jejuni. Subsequently, based on the target yclQ, we developed of a CRISPR/Cas12a-based platform for fluorescence visualization and nucleic acid test strips. The RAA-CRISPR/Cas12a system demonstrates the ability to detect C. jejuni at 1.8 CFU/mL within 50 min. Compared to PCR (1.8 × 101 CFU/mL), the RAA and RAA-CRISPR/Cas12a assay showed higher sensitivity. The detection results of the actual samples were consistent with those of the isolation and culture procedures. In conclusion, the RAA-CRISPR/Cas12a system, based on the target yclQ, demonstrates significant potential for the rapid and accurate detection of C. jejuni in food.

NIR-driven multifunctional PEC biosensor based on aptamer-modified PDA/MnO2 photoelectrode for bacterial detection and inactivation

Sensitive detection and effective inactivation of bacteria are essential in preventing foodborne bacterial infection that poses a significant threat to human health. Herein, a near-infrared (NIR)-driven multifunctional photoelectrochemical (PEC) biosensor was constructed for detection and inactivation of S. aureus. Based on the covalent bonding between amine and carboxyl groups, carboxyl-functionalized SA31 aptamer was immobilized on the PDA/MnO2 photoelectrode. In the presence of S. aureus, SA31 aptamer can specifically capture S. aureus, causing the decrease of photocurrent signal owing to steric hindrance effect. Leveraging photocurrent-off signal, there existed a satisfied linear relationship between the photocurrent variation and the logarithm of S. aureus concentration, achieving a wide linear range from 10 to 107 CFU/mL with a low detection limit of 2.0 CFU/mL. Notably, PDA/MnO2 with peroxidase-like activity facilitated the catalytic oxidation of S. aureus with assistance of hydrogen peroxide (H2O2) to cause the inactivation of S. aureus. Desorption of inactivated S. aureus from the photoelectrode led to a recovery of photocurrent signal, enabling a "signal on" switch. Simultaneously, the excellent photothermal performance of the PDA/MnO2 converted light energy into heat energy under the irradiation of NIR light (808 nm, 1.5 W/cm2), triggering the synergistic antibacterial effect against S. aureus (97.36%). This work provides a novel strategy for fabricating the detection and inactivation of bacteria in practical applications.

Effect of concurrent infection of Helicobacter pylori with Toxoplasma gondii infection on gastric pathology

BackgroundToxoplasma gondii (T. gondii) and Helicobacter pylori (H. pylori) are among the most prevalent foodborne parasitic and bacterial infections worldwide. However, the concurrent impact of coinfection on gastric pathology has yet to be studied in depth. The effect of coinfection generally either adds a synergetic or antagonistic impact; we aimed in the current work to assess the impact of T. gondii coinfection on the progression of H. pylori-associated gastric pathology and reporting H. pylori virulent strains. The study was conducted on 82 patients complaining of persistent gastrointestinal symptoms with failed treatment response and prone to endoscopy. They were subjected to stool examination to detect H. pylori antigen, serological screening for latent toxoplasmosis, endoscopy, histopathological examination, and molecular detection of H. pylori virulence strains in gastric biopsies. Out of the 82 patients, 62 patients were positive for H. pylori antigen in stool and 55 patients confirmed positivity by histopathology; out of them, 37 patients had isolated Vac As1 variants, 11 patients had combined Vac As1 and Cag A variants, and 7 patients had combined Vac As1, Cag A and VacAs2 variants. Patients with the combined two or three variances showed significantly deteriorated histopathological features than patients with a single Vac As1 variant (P < 0.05). Latent toxoplasmosis was positive among 35/82 patients. Combined H. pylori and Toxoplasma gondii infection had significantly marked inflammation than patients with isolated infection (P < 0.05). Conclusion: Screening for toxoplasmosis among H. pylori-infected patients is recommended as it is considered a potential risk factor for gastric inflammation severity. H. pylori gastric inflammation may be heightened by Toxoplasma coinfection.

Inferring molecular mechanisms of host-microbe-drug interactions in the human gastrointestinal tract

This study aimed to elucidate the metabolic interplay between food-borne bacteria, gut methanogens, and probiotic bacteria using the host-microbe-drug interactome. This study also aimed to identify suitable drug combinations that could effectively combat food-borne infections without adversely affecting the normal gut microbes. In this study, the system medicine framework comprised 2654 edges and 1609 nodes, with 1370 interacting human genes. Through network modeling analysis, we identified interactions among 39 human target genes for food-borne bacteria, 11 targets for gut methanogens, and nine targets for probiotic bacteria. Gut methanogens target common human genes for their pathophysiological functions. Linoleic acid has emerged as a crosstalk metabolite that determines the abundance of foodborne bacteria. Gut microbes commonly share butyric acid, CO3, and formaldehyde as metabolic precursors. Most antibiotics interact with human genes that target the gut methanogens and probiotic bacteria. Our study identified fusidic acid, nabiximol, oxacillin, ampicillin, phenoxymethylpenicillin, and cefdinir as repurposable antibiotics against foodborne bacterial infections. Chloroquine, an antimalarial drug, has been suggested as a potential repurposable drug for foodborne infections, owing to its indirect association with many foodborne bacteria via host-mediated interactions. Thus, our system medicine framework could potentially aid in suggesting repurposable antibiotics against food-borne bacterial infections, without affecting beneficial microbes in the human gastrointestinal tract.

Prevalence and antibiotic susceptibility of Listeria innocua in seafood from selected markets of Lagos, Nigeria

Listeria is a bacterial genus that is widely distributed in fish and fishery products and is a vehicle for food-borne bacterial infections and intoxications. Listeria innocua, though considered nonpathogenic, is a close relative to L. monocytogenes a known food-borne pathogen. It has been implicated in the transfer of antimicrobial-resistant genes. Therefore, this study investigates the prevalence of Listeria innocua and its antimicrobial susceptibility pattern in seafood found in Badagry, Iyana Ipaja, Liverpool, Makoko and Mushin, Nigeria. A total of 500 samples comprising of fresh and smoked blue whiting, croaker and shrimps were collected aseptically from retail outlets across Lagos. Culture, biochemical and sugar tests were carried out to identify L. innocua. 16S rRNA gene sequencing was conducted to confirm the isolates as L. innocua. The antimicrobial susceptibility testing was determined by the disk diffusion assay. Out of 500 seafood samples analysed, 36 (7.2%) were positive for Listeria innocua. Raw croaker had the highest occurrence of 13.0%. The antimicrobial susceptibility test revealed that all isolates were resistant to ceftazidime and cloxacillin. However, high sensitivities to ofloxacin (83.3%) and erythromycin (72.2%) were exhibited by the isolates. The recovery of these antimicrobial-resistant Listeria innocua strains in the seafood samples analysed warrants the need for suitable control procedures as this could constitute a great risk to public health.

Pathogenic E. coli in the Food Chain across the Arab Countries: A Descriptive Review.

Foodborne bacterial infections caused by pathogens are a widespread problem in the Middle East, leading to significant economic losses and negative impacts on public health. This review aims to offer insights into the recent literature regarding the occurrence of harmful E. coli bacteria in the food supply of Arab countries. Additionally, it aims to summarize existing information on health issues and the state of resistance to antibiotics. The reviewed evidence highlights a lack of a comprehensive understanding of the extent to which harmful E. coli genes are present in the food supply of Arab countries. Efforts to identify the source of harmful E. coli in the Arab world through molecular characterization are limited. The Gulf Cooperation Council (GCC) countries have conducted few surveys specifically targeting harmful E. coli in the food supply. Despite having qualitative data that indicate the presence or absence of harmful E. coli, there is a noticeable absence of quantitative data regarding the actual numbers of harmful E. coli in chicken meat supplies across all Arab countries. While reports about harmful E. coli in animal-derived foods are common, especially in North African Arab countries, the literature emphasized in this review underscores the ongoing challenge that harmful E. coli pose to food safety and public health in Arab countries.

Genomic Characterization of Salmonella enterica Resistant to Cephalosporin, Quinolones, And Macrolides.

Salmonella enterica subsp. enterica (Salmonella), one of the most common causes of bacterial foodborne infections, causes salmonellosis, which is usually self-limiting. However, immunocompromised individuals and children often require antimicrobial therapy. The first line of treatment includes fluoroquinolones, to which Salmonella has emerging resistance worldwide. In fact, the WHO classified fluoroquinolone-resistant Salmonella as a high-priority pathogen. Salmonella carrying genes such as blaCTX and blaCMY can show resistance to cephalosporins which are also regularly used for treatment. This study focused on determining the antimicrobial resistance of 373 Salmonella isolates, collected from various foods, humans, and animals, as well as the environmental sludge between 2005 and 2020 in Türkiye. Phenotypic analysis of the resistance was determined by disk diffusion method. Isolates resistant to any of the following: ciprofloxacin, pefloxacin, azithromycin, and ceftriaxone were tested for the presence of quinolone, beta-lactamase, and/or macrolide resistance genes by PCR and gel electrophoresis. Five multi-drug-resistant isolates were then further whole genome sequenced and analyzed. More than 32% (n = 120) of the isolates showed resistance to fluoroquinolones by disc diffusion. A significant number of quinolone-resistant isolates are presented with mutated parC and gyrA. Furthermore, 42% (n = 106) of the isolates were resistant to azithromycin and 10% of them harbored mphA gene. On the bright side, only eight isolates showed resistance to ceftriaxone. Overall, we observed an increase in the number of isolates showing resistance to fluoroquinolones and azithromycin over the years and low resistance to ceftriaxone.

A Bacteriophage Cocktail Reduces Five Relevant Salmonella Serotypes at Low Multiplicities of Infection and Low Temperatures.

Salmonella are important pathogenic bacteria and, following Campylobacter, they are the second most common cause of bacterial foodborne infections worldwide. To reduce the presence of bacteria along the food chain, the application of bacteriophages (phages) may be a promising tool. In this study, the lytic properties of six phages against five relevant Salmonella serotypes (S. Enteritidis, S. Typhimurium, S. Infantis, S. Paratyphi B and S. Indiana) were analyzed. Three phages were able to lyse all five serotypes. We determined the lytic potential of each phage on indicator strains in vitro at room temperature (RT) and at 37 °C using low multiplicities of infection (MOIs). Most phages reduced their host more efficiently at RT than at 37 °C, even at the lowest MOI of 0.001. Following this, the lytic activity of a cocktail comprising five phages (MOI = 0.1) was examined with each of the five serotypes and a mix of them at RT, 15, 12, 10, 8 and 6 °C. All cultures of single serotypes as well as the mixture of strains were significantly reduced at temperatures as low as 8 °C. For single serotypes, reductions of up to 5 log10 units and up to 2.3 log10 units were determined after 6 h (RT) and 40 h (8 °C), respectively. The mixture of strains was reduced by 1.7 log10 units at 8 °C. The data clearly suggest that these phages are suitable candidates for biocontrol of various Salmonella serotypes under food manufacturing conditions.

Porcine carcasses as an underestimated source of antimicrobial resistant Campylobacter coli.

Campylobacteriosis is the most common human foodborne bacterial infection worldwide and is caused by bacteria of the Camplylobacter genus. The main source of these bacteria is poultry, but other food-producing animals such as pigs are also responsible for human infections. An increasing number of strains with resistance to fluoroquinolones and other antimicrobials such as macrolides were recently noted. The aim of the study was to investigate Campylobacter contamination of porcine carcasses and determine the antimicrobial resistance of the obtained isolates. A total of 534 swabs from carcasses of pigs slaughtered in Poland during 2019-2022 were tested for Campylobacter spp. Campylobacter was detected in 164 (30.7%) carcasses; among them 149 (90.8%) were classified as C. coli and the remaining 15 (9.2%) samples were C. jejuni-positive. Because a low number of C. jejuni isolates were identified, only the C. coli isolates were subjected to antimicrobial resistance analysis. The majority of these isolates were resistant to streptomycin (94.0%), ciprofloxacin (65.8%) and tetracycline (65.1%). A total of 94 (63.1%) strains displayed antimicrobial multiresistance patterns and were mainly resistant to fluoroquinolones, aminoglycosides and tetracyclines (74; 49.7% of the isolates tested). The obtained results showed that pig carcasses may be contaminated with antimicrobial-resistant C. coli.

Prevalence, virulence gene profile and antibiogram of Campylobacter jejuni from fresh vegetables in Mymensingh, Bangladesh

This study aimed to investigate Campylobacter jejuni, a major cause of food-borne bacterial infections worldwide, in fresh vegetables from five upzillas (Mymensingh, Trishal, Bhaluka, Muktagacha, and Fulbaria) in the Mymensingh district between July 2020 and April 2023. Using cultural, biochemical, and molecular techniques, 100 fresh vegetable samples (including tomato, carrot, cucumber, green chili, and coriander) were examined for C. jejuni. The isolates were further tested for virulence genes and antimicrobial susceptibility. Out of the 100 samples, 23% were confirmed as C. jejuni, by 16S rRNA gene-based polymerase chain reaction and all were found to be virulent with cytolethal distending toxins (cdtA, cdtB and cdtC genes). Antibiotic susceptibility testing revealed resistance to amoxicillin (47.83%), tetracycline (43.48%), and streptomycin (39.13%) among the isolates. However, ceftriaxone and ciprofloxacin were effective against 47.83% and 43.48% of the isolates, respectively. Moreover, 52.17% of the isolates were sensitive to erythromycin. Alarmingly, 34.78% of the C. jejuni isolates exhibited multidrug resistance (MDR) with eight different antibiotic resistance patterns, including four MDR patterns. These findings highlight the presence of virulent and antibiotic-resistant C. jejuni in fresh vegetables, emphasizing the need for monitoring and control to ensure food safety and public health issues. Asian Australas. J. Food Saf. Secur. 2023, 7 (2), 62-72

Cell membrane-coated nanoparticles: An emerging antibacterial platform for pathogens of food animals.

Bacterial pathogens of animals impact food production and human health globally. Food animals act as the major host reservoirs for pathogenic bacteria and thus are highly prone to suffer from several endemic infections such as pneumonia, sepsis, mastitis, and diarrhea, imposing a major health and economical loss. Moreover, the consumption of food products of infected animals is the main route by which human beings are exposed to zoonotic bacteria. Thus, there is excessive and undue administration of antibiotics to fight these virulent causative agents of food-borne illness, leading to emergence of resistant strains. Thus, highprevalence antibiotic-resistant resistant food-borne bacterial infections motivated the researchers to discover new alternative therapeutic strategies to eradicate resistant bacterial strains. One of the successful therapeutic approach for the treatment of animal infections, is the application of cell membrane-coated nanoparticles. Cell membranes of several different types of cells including platelets, red blood cells, neutrophils, cancer cells, and bacteria are being wrapped over the nanoparticles to prepare biocompatible nanoformulations. This diversity of cell membrane selection and together with the possibility of combining with an extensive range of nanoparticles, has opened a new opportunistic window for the development of more potentially effective, safe, and immune evading nanoformulations, as compared to conventionally used bare nanoparticle. This article will elaborately discuss the discovery and development of novel bioinspired cell membrane-coated nanoformulations against several pathogenic bacteria of food animals such as Klebsiella pneumoniae, Escherichia coli, Staphylococcus aureus, Salmonella enteritidis, Campylobacter jejuni, Helicobacter pylori, and Group A Streptococcus and Group B Streptococcus.

An Arsenal of Multiple Antimicrobial Resistance, Toxins, and Virulence Factors in Gram-Negative Bacterial Isolates from Food - A Formidable Combination!

Infectious diseases caused by pathogenic members of the family Enterobacteriaceae cause mortality and morbidity in humans. These are mediated mainly via toxins or virulence factors in combination with multiple antimicrobial resistance (MAR) against antimicrobials intended to treat infections. Resistance can be transferred to other bacteria, possibly also in association with other resistance determinants and/or virulence properties. Food-borne bacterial infections are one of the major causes of infections in humans. The level of scientific information about foodborne bacterial infections in Ethiopia is very limited at best. Bacteria were isolated from commercial dairy foods. These were cultured in appropriate media for identification at the family level (Enterobacteriaceae) based on Gram-negative, catalase-positive, oxidase-negative, and urease-negative phenotypes, followed by testing for the presence of virulence factors and resistance determinants to various antimicrobial classes using phenotypic and molecular tests. Twenty Gram-negative bacteria isolated from the foods were found to be resistant to almost all antimicrobials belonging to the phenicol, aminoglycoside, fluoroquinolone, monobactam, and β-lactam classes. All of them were multiple-drug-resistant. The resistance to the β-lactams was due to the production of β-lactamases and were also mostly resistant to some of the β-lactam/β-lactamase inhibitor combinations. Some isolates also contained toxins. This small-scale study demonstrated the presence, in the isolates, of high levels of virulence factors and resistance to major antimicrobials that are in clinical use. Most treatment being empirical, there can be not only a high degree of treatment failure but also the likelihood for further development and dissemination of antimicrobial resistance. Since dairy foods are animal products, there is an urgent need to control animal-food-human transmission mechanisms, restrict antimicrobial use in animal agriculture, and improve clinical treatment from the usual empirical treatment to more targeted and effective treatment.

Evaluation of bacteriological profile of meat contact surfaces, handling practices of raw meat and its associated factors in butcher shops of Arba Minch town, southern Ethiopia-A facility based cross sectional study

BackgroundMeat is subjected to contamination from a range of sources throughout animal slaughter and its sale. The demand for meat products in Ethiopia has been increased dramatically; especially the consumption of fresh chilled meat becomes a status of symbol.ObjectivesThis study aimed to evaluate the bacteriological profile of meat contact surfaces, raw meat handling practices, and its associated factors in butcher shops located in Arba Minch town, southern Ethiopia.Methods and MaterialsA facility-based cross-sectional study was carried out among meat handlers in butcher shops in Arba Minch town from November to December 2020. A pre-tested and semi-structured interviewer-administered questionnaire was used to collect the data on workers meat handling practices and the sterile swab was used to collect samples from selected meat contact surfaces for bacteriological analysis. Statistical Package for Social Sciences (SPSS) version 21 was used for data analysis. Binary logistic regression analysis was utilized to assess the presence and degree of association between raw meat handling practice and independent variables. Adjusted odds ratio with a 95% confidence interval at P-value < 0.05 was considered statistically significant.Result and ConclusionThis study revealed the knowledge and handling practice gap among meat handlers of butcher shops. Knowledge of food handling hygiene has shown significant association with handling practice [AOR = 4.5 (1.182,17.202)]. The median total viable count of bacterial loads from the swab samples of butchers’ hands, knives, and the tables was 5.60 ± 0.80, 5.60 ± 1.00, 5.70 ± 1.00 log10 Colony-forming unit (CFU)/cm2, respectively. Escherichia coli was the predominant isolate 34(68%) followed by Staphylococcus species 28(56%) and Salmonella species 19(38%). The median total bacterial load obtained from the samples exceeds the acceptable value of less than 5.0 log10 CFU/cm2 on fresh meat. This indicates the need for improvement in the meat handling and processing chain to safeguard the public health against the risks of foodborne bacterial infections.

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.

1367. Resistance to Ceftriaxone and Ciprofloxacin in Nontyphoidal Salmonella from Humans and Relatedness to Isolates from Animal Sources

Abstract Background Nontyphoidal Salmonella (NTS) is a leading cause of foodborne bacterial infections. Annually, ∼200,000 antimicrobial-resistant (AMR) NTS illnesses occur in the United States. NTS infections resistant to ceftriaxone and ciprofloxacin, drugs used for the treatment of severe infections, are a growing concern. Methods We identified patient NTS isolates submitted to the Pennsylvania Bureau of Laboratories by two hospitals from the same health system during 2018–2020. All were tested by broth microdilution for susceptibility to antibiotics tracked by the National Antimicrobial Resistance Monitoring System and analyzed by whole-genome sequencing. We identified resistance mechanisms and plasmids with ResFinder and PlasmidFinder, respectively, and compared each isolate in selected serotypes against the PulseNet database to identify genetic relatedness within ≤5 allele differences to non-human sequences uploaded during 2017–2021. Results Of 164 human NTS analyzed for susceptibility, 28 (17%) had decreased susceptibility to ciprofloxacin (DSC) [MIC ≥0.12 µg/mL] while 6 (3.7%) were ceftriaxone-resistant. AMR varied by serotype; 8 (50%) S. Infantis and 16 (42%) Enteritidis had DSC, representing 86% of all isolates with DSC (Figure). Six ceftriaxone-resistant isolates had genes that confer resistance to third-generation cephalosporins including blaCMY−2 in 1 Dublin and 2 Typhimurium and blaCTX-M-65 in 3 Infantis isolates. The 3 Infantis isolates also had a mutation in gyrA that results in DSC, plus a known transmissible plasmid IncFIB(pN55391) linked to multiple resistance genes. An Infantis isolate was related to a chicken meat isolate and a Hadar isolate was related to isolates from 3 animals and 3 meat sources. One Dublin isolate was related to 2 isolates from beef in Pennsylvania. Figure.Percent of antimicrobial resistance in nontyphoidal Salmonella (NTS) clinical isolates (n=164) submitted to public health authorities by two hospital systems in Pennsylvania, 2018–2020. Multidrug resistance (MDR) was defined as resistance to ≥3 of the 9 antimicrobial classes tested for NTS clinical isolates. Resistance to ceftriaxone (AXO), a third-generation cephalosporin preferred for treating severe infections in children, was over 5% and 19% in serotypes S. Typhimurium and S. Infantis, respectively. Half (8/16) of Infantis isolates and 42% (16/38) of Enteritidis isolates had decreased susceptibility to ciprofloxacin (DSC). Conclusion Ceftriaxone resistance and DSC in NTS from patients in Pennsylvania varied by serotype and some isolates harbored blaCMY−2 and blaCTX-M-65 genes. Dissemination of mechanisms that confer resistance to ceftriaxone and DSC is concerning as is the genetic relatedness of isolates from human and animal sources. Our study highlights the need for enhanced One Health AMR monitoring combined with a review of animal production and food processing practices. Disclosures All Authors: No reported disclosures.

Codex Alimentarius Guidelines for Risk Analysis of Foodborne Antimicrobial Resistance Are Incompatible with Available Surveillance Data

Foodborne antimicrobial-resistant (AMR) microorganisms are a global food safety concern. Antimicrobial drug use (AMU) in livestock may increase the risk of resistant foodborne bacterial infections in humans via contaminated animal products. Consequently, countries have implemented different livestock AMU restriction policies, opening the potential for trade disputes. AMR risk equivalence between countries with different AMU policies must be established by using scientifically justified risk assessments. The Codex Alimentarius Commission's Guidelines for Risk Analysis of Foodborne Antimicrobial Resistance (AMR Codex) recommends an approach that requires quantification of detailed information, for which, in many instances, little to no data exist. Using AMR Salmonella exposure from beef consumption as an example, we demonstrate the difficulty of implementing the AMR Codex by comparing key regionally specific parameters within the United States and European Union, two regions with substantial beef production and consumption, robust foodborne pathogen sampling and surveillance systems, and different AMU policies. Currently, neither region fully captures data for key regional variables to populate a detailed risk assessment as outlined in the AMR Codex, nor are they able to adequately link AMU in livestock to AMR infections in humans. Therefore, the AMR Codex guidelines are currently aspirational and not a viable option to assess the impact of livestock AMU reductions on the human health risk of AMR salmonellosis from beef or produce regionally comparable estimates of risk. More flexible risk assessment guidelines that more directly link livestock AMU to human health risk and are amenable to currently available data are needed to allow for country variations and to calculate comparable regional risk estimates, which can be used to guide international trade policy.

Molecular Epidemiology and Virulence of Non-Typhoidal Salmonella in Armenia.

In this work, we analysed human isolates of nontyphoidal Salmonella enterica subsp. enterica (NTS), which were collected from salmonellosis cases in Armenia from 1996 to 2019. This disease became a leading food-borne bacterial infection in the region, with the younger age groups especially affected. The isolates were characterised by serotyping, Enterobacterial Repetitive Intergenic Consensus (ERIC-PCR) typing, and whole genome sequencing (WGS). The main serotypes were S. Typhimurium, S. Enteritidis, and S. Arizonae. ERIC-PCR indicated a high degree of clonality among S. Typhimurium strains, which were also multidrug-resistant and produced extended spectrum beta-lactamases. During the study period, the frequency of S. Typhimurium and S. Arizonae isolations decreased, but with the increase in S. Enteritidis and other NTS. A total of 42 NTS isolates were subjected to WGS and explored for virulence-related traits and the corresponding genetic elements. Some virulence and genetic factors were shared by all NTS serotypes, while the main differences were attributed to the serotype-specific diversity of virulence genes, SPIs, virulence plasmids, and phages. The results indicated the variability and dynamics in the epidemiology of salmonellosis and a high virulence potential of human NTS isolates circulating in the region.

Zoological and Biological Role of Parasites, Pathogens, Worms in Food Web and Future Perspectives

Instructive approaches for testing emerging malaria vaccine candidates could potentially have a lot of translational value. The potential of genetically altered Plasmodium species that do not grow beyond the liver stages, in triggering a protective immunity. Giardia-lamblia, Ascaris-lumbricoides, Trichuris-trichiura, Schistosoma species and Entamoeba-histolytica are most intestinal worm parasites around worldwide. Amebiasis is caused by Entamoeba histolytica invading the intestinal mucosa and causing severe mortality and morbidity. Babesiosis is tick borne infectious disease which causes anaemia, fever, haemoglobinuria, and frailty in the animals. Various bacterial species have been found in fish’s natural habitats. Bacterial colonies can be seen on fish’s gills and skin as a result of persistent contact to unclean water, whereas polluted water or food might harm the gastrointestinal tract. Salmonella nontyphoidalis is the most common zoonotic bacterial food borne infection in humans. Salmonellae are common around the world, and they are the most common pathogenic bacteria in both humans and animals. Engineering the genes which code for pathogenicity effectors and host adaptability could be the key to completely identifying the causal relationship among a gene deficiency and infections in organoids.

Recent Genetic Changes Affecting Enterohemorrhagic Escherichia coli Causing Recurrent Outbreaks.

ABSTRACTEnterohemorrhagic E. coli (EHEC) is responsible for significant human illness, death, and economic loss. The main reservoir for EHEC is cattle, but plant-based foods are common vectors for human infection. Several outbreaks have been attributed to lettuce and leafy green vegetables grown in the Salinas and Santa Maria regions of California. Bacteria causing different outbreaks are mostly not close relatives, but one group of closely-related O157:H7 has caused several of them. This unusual pattern of recurrence may have some genetic basis. Here I use whole-genome sequences to reconstruct the genetic changes that occurred in the recent ancestry of this EHEC. In a short period of time corresponding to little genetic change, there were several changes to adhesion-related sequences, mainly adhesins. These changes may have greatly altered the adhesive properties of the bacteria. Possible consequences include increased persistence of cattle infections, more bacteria shed in cattle feces, and greater virulence in humans. Similar constellations of genetic change, which are detectable by current sequencing-based surveillance, may identify other bacteria that are particular threats to human health. In addition, the Santa Maria subclade carries a nonsense mutation affecting ArsR, a repressor of genes that confer resistance to arsenic and antimony. This suggests that the persistent source of Santa Maria contamination is located in an area with arsenic-contaminated groundwater, a problem in many parts of California. This inference may aid identification of the reservoir of EHEC, which would greatly aid mitigation efforts.IMPORTANCE Food-borne bacterial infections cause substantial illness and death. Understanding how bacteria contaminate food and cause disease is important for combating the problem. Closely-related E. coli, likely originating in cattle, have repeatedly caused outbreaks spread by vegetables grown in California. Such recurrence is atypical, and might have a genetic basis. The genetic changes that occurred in the recent ancestry of these E. coli can be reconstructed from their DNA sequences. Several mutations affect genes involved in bacterial adhesion. These might affect persistence of infection in cattle, quantity of bacteria in their feces, and human disease. They also suggest a way of detecting dangerous bacteria from their genome sequences. Furthermore, a subgroup carries a mutation affecting the regulation of genes conferring arsenic resistance. This suggests that the reservoir for contamination utilizes groundwater contaminated with arsenic, a problem in parts of California. This observation may be an aid to locating the persistent reservoir of contamination.