Foodborne Outbreaks Research Articles

Antimicrobial and Phylogenomic Characterization of Bacillus cereus Group Strains Isolated from Different Food Sources in Italy.

Background:Bacillus cereus is a widespread environmental Gram-positive bacterium which is especially common in soil and dust. It produces two types of toxins that cause vomiting and diarrhea. At present, foodborne outbreaks due to Bacillus cereus group bacteria (especially Bacillus cereus sensu stricto) are rising, representing a serious problem in the agri-food supply chain. Methods: In this work, we analyzed 118 strains belonging to the Bacillus cereus group, isolated from several food sources, for which in vitro and in silico antibiotic resistance assessments were performed. Results: Many strains showed intermediate susceptibility to clindamycin, erythromycin, and tetracycline, suggesting an evolving acquisition of resistance against these antibiotics. Moreover, one strain showed intermediate resistance to meropenem, an antibiotic currently used to treat infections caused by Bacillus cereus. In addition to the phenotypic antimicrobial resistance profile, all strains were screened for the presence/absence of antimicrobial genes via whole-genome sequencing. There was inconsistency between the in vitro and in silico analyses, such as in the case of vancomycin, for which different isolates harbored resistance genes but, phenotypically, the same strains were sensitive. Conclusions: This would suggest that antibiotic resistance is a complex phenomenon due to a variety of genetic, epigenetic, and biochemical mechanisms.

Search for Listeria spp. in fresh type sausages sold in the agreste region of Pernambuco and its importance for public health

Foodborne diseases (FBDs) are considered illnesses related to the ingestion of foods contaminated with physical, chemical, or pathogenic microorganisms. The genus Listeria spp. is responsible for the foodborne illness listeriosis. This pathology poses a significant public health risk due to its high mortality and sequelae, particularly affecting immunocompromised patients, pregnant women, the elderly, and children. The purpose of this study was to evaluate the presence of Listeria spp. in commercial fresh sausages. Eighteen samples of raw fresh sausages were collected and divided into three portions. Some were subjected to thermal treatments at two different temperatures (55ºC and 74ºC), while another portion remained raw, totaling 54 samples. Listeria monocytogenes and Listeria spp. research and isolation were conducted according to ISO 11290-1:2017. Biochemical tests were performed using the Gram staining methodology on characteristic strains. Additionally, moisture and ash determination and statistical analysis of the results were conducted. Among the 54 samples analyzed, approximately eight isolates showed colonies with characteristics suggestive of Listeria spp., thus not complying with the microbiological standards established by Resolution of the Collegiate Board (RDC) 331/2019 of the National Health Surveillance Agency (ANVISA). The presence of L. innocua and other pathogenic bacterial species in the samples is concerning, as there is a likelihood of microorganisms proliferating in the equipment and utensils used in sausage preparation, thus spreading pathogens to other products and increasing the risk of foodborne outbreaks and infections.

Knowledge, Attitude and Practice of Food Handlers Toward Food-Borne Infections; A Survey During War

Background: food safety knowledge attitude and practice among food handlers during war catastrophe are important measures in the prevention of food borne diseases outbreaks. Aim: to assess knowledge attitude and practice of food handlers toward food borne infections. Method: a cross-sectional descriptive observational study was conducted within one months. It involved 36 food handlers in different positions. Total sampling was done. Data were collected by interview-based questionnaire and analyzed by SPSS version 27.0. Results: the total score of the employee’s level of knowledge was (414 / 63.8%) points which indicate moderate level. The score of attitudes was (253 / 63.8%) points that reported moderate level of attitude also. (497 / 23%) points were scored for the practice, and poor level was showed. Conclusion: Ministry of health should consider these factors for enhancing food handlers’ knowledge and increase training and supervision on food safety practices to reduce foodborne diseases and outbreaks.

Ingestion of Bacillus cereus spores dampens the immune response to favor bacterial persistence

Strains of the Bacillus cereus (Bc) group are sporulating bacteria commonly associated with foodborne outbreaks. Spores are dormant cells highly resistant to extreme conditions. Nevertheless, the pathological processes associated with the ingestion of either vegetative cells or spores remain poorly understood. Here, we demonstrate that while ingestion of vegetative bacteria leads to their rapid elimination from the intestine of Drosophila melanogaster, a single ingestion of spores leads to the persistence of bacteria for at least 10 days. We show that spores do not germinate in the anterior part of the intestine which bears the innate immune defenses. Consequently, spores reach the posterior intestine where they germinate and activate both the Imd and Toll immune pathways. Unexpectedly, this leads to the induction of amidases, which are negative regulators of the immune response, but not to antimicrobial peptides. Thereby, the local germination of spores in the posterior intestine dampens the immune signaling that in turn fosters the persistence of Bc bacteria. This study provides evidence for how Bc spores hijack the intestinal immune defenses allowing the localized birth of vegetative bacteria responsible for the digestive symptoms associated with foodborne illness outbreaks.

Global epidemiology, genotype distribution and coinfection rate of Human Aichi virus: A systematic review

BackgroundAcute gastroenteritis is a major health concern for all age groups and accounts for more than 2.5 million deaths annually in children under five years old. Human Aichi virus causes acute gastroenteritis and is associated with foodborne outbreaks. Little is known about its pathogenicity, evolution, and geographical distribution. ObjectiveThis study aimed to describe the global seroprevalence of AiV-1 and its genotype distribution, track outbreaks, and estimate co-infection rates with other viral gastroenteritis. MethodsA comprehensive systematic search of the epidemiological aspects of AiV-1 was conducted using peer-reviewed English original articles indexed in several scientific database libraries since its first detection in Japan until October 2022. A total of 55 published studies were included in the final analysis based on the inclusion criteria. ResultThe global prevalence of AiV-1 was 1.45 %. To date, nine AiV-1 outbreaks were reported following the first oyster-associated outbreak in Japan between 1987 and 1991. AiV-1 genotype A has a worldwide distribution, whereas genotypes B and C have a pattern of geo-localization. The gradual and significant increase of AiV-1 seroprevalence with age was reported in all studies. The most predominant viruses causing viral coinfection among AiV-1-infected patients were Norovirus (36.55 %), Rotavirus (18.91 %), and Sapovirus (15.13 %). Coinfections with Norovirus (p-value 0.003), Rotavirus (p = 0.007), and Human Astrovirus (p = 0.032) were significantly correlated with AiV-1 coinfection. ConclusionThis was the first comprehensive systematic review of AiV-1. Although AiV-1 has a low global prevalence, it can be considered a health concern due to its association with childhood gastroenteritis.

Growth of Listeria monocytogenes in fresh vegetables and vegetable salad products: An update on influencing intrinsic and extrinsic factors.

The ability of foodborne pathogens to grow in food products increases the associated food safety risks. Listeria monocytogenes(Lm) is a highly adaptable pathogen that can survive and grow under a wide range of environmental circumstances, including otherwise inhibitory conditions, such as restrictive cold temperatures. It can also survive long periods under adverse environmental conditions. This review examines the experimental evidence available for the survival and growth of Lm on fresh vegetables and ready-to-eat vegetable salads. Published data indicate that, depending on certain intrinsic (e.g., nutrient composition) and extrinsic factors (e.g., storage temperature, packaging atmosphere), Lm can survive on and in a wide variety of vegetables and fresh-cut minimally processed vegetable salads. Studies have shown that temperature, modified atmosphere packaging, relative humidity, pH, water activity, background microbiota of vegetables, microbial strain peculiarities, and nutrient type and availability can significantly impact the fate of Lm in vegetables and vegetable salads. The influence of these factors can either promote its growth or decline. For example, some studies have shown that background microbiota inhibit the growth of Lm in vegetables and minimally processed vegetable salads, but others have reported a promoting, neutral, or insignificant effect on the growth of Lm. A review of relevant literature also indicated that the impact of most influencing factors is related to or interacts with other intrinsic or extrinsic factors. This literature synthesis contributes to the body of knowledge on possible strategies for improving food safety measures to minimize the risk of Lm-associated foodborne outbreaks involving vegetables and vegetable salads.

Droplet Digital PCR for Precise Quantification of Human Norovirus in Shellfish Associated with Gastroenteritis Illness

Norovirus is the predominant cause of viral gastroenteritis globally with foodborne outbreaks commonly reported. Filter-feeding bivalve molluscan shellfish can become contaminated with norovirus when grown in waters impacted by inadequately treated effluent wastewater, overflows, or other human fecal sources. Contaminated shellfish pose a significant risk to consumers, because combined with a low norovirus infectious dose, oysters and mussels are often eaten raw or lightly cooked resulting in no or minimal virus inactivation, respectively. In addition, shellfish contamination has significant economic impacts on the seafood industry. To improve risk assessments, reverse transcription (RT)-digital droplet PCR (ddPCR) was used to determine the precise norovirus concentrations in 20 shellfish samples, all positive for norovirus genogroup I and/or II (GI or GII) by RT-qPCR, and associated with reported norovirus illness in New Zealand. Using RT-ddPCR, total norovirus GI and/or GII concentrations in shellfish ranged between 44 and 4,630 genome copies (GC)/g digestive tissue. Importantly, 40% (8/20) of shellfish samples contained a total norovirus concentration less than 200 GC/g digestive tissue. In parallel, RNase treatment was applied, prior to viral extraction to remove free RNA, which subsequently led to average reductions in norovirus GC/g concentration of 37.1% and 19.4% for GI and GII, respectively. These RT-ddPCR data provide valuable evidence for risk assessment of contaminated shellfish and evaluation of safety guidelines and highlight issues associated with setting a safe threshold of norovirus in shellfish.

Helical ultrastructure of the L-ENA spore aggregation factor of a Bacillus paranthracis foodborne outbreak strain

In pathogenic Bacillota, spores can form an infectious particle and can take up a central role in the environmental persistence and dissemination of disease. A poorly understood aspect of spore-mediated infection is the fibrous structures or ‘endospore appendages’ (ENAs) that have been seen to decorate the spores of pathogenic Bacilli and Clostridia. Current methodological approaches are opening a window on these long enigmatic structures. Using cryoID, Alphafold modelling and genetic approaches we identify a sub-class of robust ENAs in a Bacillus paranthracis foodborne outbreak strain. We demonstrate that L-ENA are encoded by a rare three-gene cluster (ena3) that contains all components for the self-assembly of ladder-like protein nanofibers of stacked heptameric rings, their anchoring to the exosporium, and their termination in a trimeric ‘ruffle’ made of a complement C1Q-like BclA paralogue. The role of ENA fibers in spore-spore interaction and the distribution of L-ENA operon as mobile genetic elements in B. cereus s.l. strains suggest that L-ENA fibers may increase the survival, spread and virulence of these strains.

Dormancy of pathogenic bacteria in the fresh produce supply chain

The increased consumption of fresh produce in the last decades has led to an escalation in the number of associated foodborne outbreaks. Various stressful conditions along the fresh produce supply chain can induce bacteria to enter a dormancy state, such as the persistence state and the viable but nonculturable (VBNC) state. Bacteria can develop an increased tolerance to a range of environmental stresses in the dormancy state and return to their normal growing state when conditions become favorable, leading to foodborne illnesses. This review will explore how bacteria contaminate fresh produce along the supply chain and the conditions that can promote the formation of dormant cells. Additionally, various options for detecting and eradicating dormant bacterial cells in the fresh produce supply chain will be discussed.

Developing a digital data platform for surveillance of food and water-borne pathogens in North East India: insight for public health advocacy.

Robust digital infrastructure is vital and the need of the hour, especially in the healthcare sector, for real-time data generation, analysis, and quick decision-making. Food- and water-borne illnesses represent a prominent cause of morbidity and mortality worldwide. India, a developing nation with diverse cultures and food practices, poses a high risk of food-borne diseases and outbreaks, yet is often underreported and ineffectively researched. Also, the unique socio-economic and environmental factors of the Northeast (NE) region contribute to the high burden of food-borne diseases. To address these trepidations, the Indian Council of Medical Research (ICMR) has undertaken a study for the surveillance of food-borne pathogens in NE India. The present study focuses on the development of a digital database system for the systematic surveillance of foodborne disease outbreaks, aiming to address the gaps in traditional surveillance methods and improve disease detection and response capabilities. The digital system integrates mobile applications, web-based platforms, and advanced analytics tools to enable real-time data collection, dissemination, and analysis of food-borne illness data. Additionally, the secure and scalable nature of the system enhances data accuracy and accessibility, making it a valuable tool for enhancing food-borne disease surveillance efforts in resource-constrained settings.

Reliable delineation of Bacillus cytotoxicus from other members of the Bacillus cereus group by MALDI-TOF MS – An extensive validation study

Bacillus cytotoxicus is classified as a thermotolerant member of the Bacillus cereus group, producing the diarrhoea causing cytotoxin K1. This species came into the focus of food microbiologists when the type strain was isolated as the cause of a fatal food-borne outbreak. However, knowledge of the role of B. cytotoxicus as a food-borne microbe and data on its prevalence in food is still limited today. One reason for this is the lack of an easy to perform method of identification at the species level other than PCR, due to the highly similar phenotype of many B. cereus group representatives. Matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS) is widely used for the identification of microorganism species. This study describes the formal validation of a MALDI-TOF MS system for a reliable differentiation between B. cytotoxicus and other members of the B. cereus group. An extensive number of well-supported individual spectra from B. cytotoxicus, several other species of the B. cereus group, and 652 other microorganism species in a taxonomically wide range served as data sets. These were used to perform the validation for two database compilations: the commercial MALDI-Biotyper version K, and an extended compilation, including reference spectra from an open collection of spectra created by several users. Using both database combinations, the obtained values fulfil the formal criteria for the targeted identification of B. cytotoxicus in accordance with a national guideline for the validation of MALDI-TOF MS parameters in food analysis, with significant improvements due to the expanded database. By using 183 single spectra from 170 isolates, created in eleven different laboratories, the number of samples significantly exceeded the sample sizes for validation currently specified for ISO 16140–4:2020 for the validation of identification methods in food microbiology by single laboratories. Therefore, the method is suitable for routine application in an accredited laboratory context.

A Bacteriophage Protein-Based Impedimetric Electrochemical Biosensor for the Detection of Campylobacter jejuni.

Campylobacter jejuni is a common foodborne pathogen found in poultry that can cause severe life-threatening illnesses in humans. It is important to detect this pathogen in food to manage foodborne outbreaks. This study reports a novel impedimetric phage protein-based biosensor to detect C. jejuni NCTC 11168 at 100 CFU/mL concentrations using a genetically engineered receptor-binding phage protein, FlaGrab, as a bioreceptor. The electrochemical impedance spectroscopy (EIS) technique was employed to measure changes in resistance upon interaction with C. jejuni. The sensitivity of the phage protein-immobilized electrode was assessed using the various concentrations of C. jejuni NCTC 11168 ranging from 102-109 colony forming units (CFU)/mL). The change transfer resistance of the biosensor increased with increasing numbers of C. jejuni NCTC 11168 cells. The detection limit was determined to be approximately 103 CFU/mL in the buffer and 102 CFU/mL in the ex vivo samples. Salmonella enterica subsp. enterica serotype Typhimurium-291RH and Listeria monocytogenes Scott A were used as nontarget bacterial cells to assess the specificity of the developed biosensor. Results showed that the developed biosensor was highly specific toward the target C. jejuni NCTC 11168, as no signal was observed for the nontarget bacterial cells.

Genomic diversity of Salmonella enterica serovar Typhimurium isolated from chicken processing facilities in New South Wales, Australia.

Contamination of poultry products by Salmonella enterica serovar Typhimurium (STm) is a major cause of foodborne infections and outbreaks. This study aimed to assess the diversity and antimicrobial resistance (AMR) carriage of STm in three chicken processing plants using genomic sequencing. It also aimed to investigate whether any particular strain types were associated with cases of human illness. Multilevel genome typing (MGT) was used to analyze 379 STm isolates from processed chicken carcasses. The diversity of chicken STm sequence types (STs) increased from MGT1 (2 STs) to MGT9 (257 STs). STs at MGT5 to MGT9 levels that were unique to one processing plant and shared among the processing plants were identified, likely reflecting the diversity of STm at their farm source. Fifteen medium resolution MGT5 STs matched those from human infections in Australia and globally. However, no STs matched between the chicken and human isolates at high resolution levels (MGT8 or MGT9), indicating the two STm populations were phylogenetically related but were unlikely to be directly epidemiologically linked. AMR genes were rare, with only a bla TEM-1 gene carried by a 95 kb IncI1 Alpha plasmid being identified in 20 isolates. In conclusion, subpopulations that were widespread in processing plants and had caused human infections were described using MGT5 STs. In this STM population, AMR was rare with only sporadic resistance to a single drug class observed. The genomic analysis of STm from chicken processing plants in this study provided insights into STm that contaminate meat chickens early in the food production chain.

Development of a cell culture-based method for detecting infectious tick-borne encephalitis virus (TBEV) in milk products

Tick-borne encephalitis outbreaks have been reported in Europe after consumption of raw milk products from infected animals. While molecular methods are commonly used in viral foodborne outbreak investigations due to their sensitivity, specificity and rapidity, there are very few methods to detect infectious tick-borne encephalitis virus (TBEV) in milk products for routine use/analyses. To address this gap, we developed a cell culture-based method to detect infectious TBEV in artificially contaminated raw goat milk and raw goat cheese, and evaluated the sensitivity of TBEV infectivity assays. Raw goat milk samples were spiked with TBEV to achieve inoculation levels ranging from 106 to 100 TCID50/mL, and Faisselle and Tomme cheese samples were spiked so their TBEV concentrations ranged from 9.28 × 105 to 9.28 × 101 TCID50 per 2.5g. To detect infectious TBEV, Vero cells were infected by raw goat milk. For cheese samples, after homogenisation and membrane filtration, Vero cells were infected with samples adsorbed on the filter (method A) or with samples eluted from the filter (method B). After 5 days, cytopathic effects (CPEs) were observed and TBEV replication in Vero cells was confirmed by an increase in the number of genome copies/mL that were detected in cell supernatant. Infected Vero cells exhibited CPEs for both milk and cheese samples. Infectious TBEV was detected to 103 TCID50/mL in raw milk samples and to 9.28 × 101 TCID50 from Faisselle samples using both methods A and B. For Tomme samples, method A was able to detect TBEV to 9.28 × 102 TCID50/2.5g and method B to 9.28 × 103 TCID50/2.5g. The number of positive samples detected was slightly higher with method A than with method B. To conclude, this qualitative cell culture-based method can detect infectious TBEV artificially inoculated into raw milk and cheese; it should be further evaluated during foodborne outbreak investigations to detect infectious TBEV from naturally contaminated milk and cheese.

MCNN_MC: Computational Prediction of Mitochondrial Carriers and Investigation of Bongkrekic Acid Toxicity Using Protein Language Models and Convolutional Neural Networks.

Mitochondrial carriers (MCs) are essential proteins that transport metabolites across mitochondrial membranes and play a critical role in cellular metabolism. ADP/ATP (adenosine diphosphate/adenosine triphosphate) is one of the most important carriers as it contributes to cellular energy production and is susceptible to the powerful toxin bongkrekic acid. This toxin has claimed several lives; for example, a recent foodborne outbreak in Taipei, Taiwan, has caused four deaths and sickened 30 people. The issue of bongkrekic acid poisoning has been a long-standing problem in Indonesia, with reports as early as 1895 detailing numerous deaths from contaminated coconut fermented cakes. In bioinformatics, significant advances have been made in understanding biological processes through computational methods; however, no established computational method has been developed for identifying mitochondrial carriers. We propose a computational bioinformatics approach for predicting MCs from a broader class of secondary active transporters with a focus on the ADP/ATP carrier and its interaction with bongkrekic acid. The proposed model combines protein language models (PLMs) with multiwindow scanning convolutional neural networks (mCNNs). While PLM embeddings capture contextual information within proteins, mCNN scans multiple windows to identify potential binding sites and extract local features. Our results show 96.66% sensitivity, 95.76% specificity, 96.12% accuracy, 91.83% Matthews correlation coefficient (MCC), 94.63% F1-Score, and 98.55% area under the curve (AUC). The results demonstrate the effectiveness of the proposed approach in predicting MCs and elucidating their functions, particularly in the context of bongkrekic acid toxicity. This study presents a valuable approach for identifying novel mitochondrial complexes, characterizing their functional roles, and understanding mitochondrial toxicology mechanisms. Our findings, that utilize computational methods to improve our understanding of cellular processes and drug-target interactions, contribute to the development of therapeutic strategies for mitochondrial disorders, reducing the devastating effects of bongkrekic acid poisoning.

Potential of bacteriophage phT4A as a biocontrol agent against Escherichia coli in food matrices

Escherichia coli is one of the most prevalent foodborne pathogens, frequently found in meat and dairy products. Current decontamination methods are often associated with changes in organoleptic characteristics, nutrient loss, and potentially harmful side effects. Furthermore, despite the array of available methods, foodborne outbreaks still frequently occur. For this reason, bacteriophages (or simply phages) emerged as a natural alternative for the biocontrol of bacterial contamination in food without altering their organoleptic properties. In this study, the potential of phage phT4A was assessed in the biocontrol of E. coli in liquid (milk) and solid (ham) food matrices. Firstly, as foods have different pH and temperature values, the influence of these parameters on phage phT4A viability was also assessed to develop an effective protocol. Phage phT4A proved to be stable for long storage periods at pH 7–8 (56 days) and temperatures of 4–37 °C (21 days). Before application of phages to inactivate pathogenic bacteria in food, previous assays were carried out in Tryptic Soy Broth (TSB) to study the dynamics of phage-bacteria interaction. Then, the antibacterial potential of phage phT4A was evaluated in the two food matrices at different temperatures (4, 10 and 25 °C). This phage was more efficient at 25 °C in all tested matrices (maximum inactivation of 6.6, 3.9 and 1.8 log CFU/mL in TSB, milk and ham, respectively) than at 10 °C (maximum decrease of 4.7, 2.1 and 1.0 log CFU/mL in TSB, milk and ham, respectively) and 4 °C (maximum reduction of 2.6 and 0.7 log CFU/mL in TSB and milk, respectively). However, the decrease of temperature from 25 °C to 10 and 4 °C prevented bacterial regrowth. The results suggest that during phage treatment, a balance between an incubation temperature that provide effective results in terms of bacterial inactivation by the phages and at the same time prevents or delays bacterial regrowth, is needed. The application of phage phT4A at a temperature of 10 °C can be an effective strategy in terms of bacterial inactivation, delaying bacterial regrowth and also reducing energy costs.

First Data on WGS-Based Typing and Antimicrobial Resistance of Human Salmonella Enteritidis Isolates in Greece.

Salmonella enterica subsp. enterica serotype Enteritidis (S. Enteritidis) is one of the major causes of foodborne infections and is responsible for many national and multi-country foodborne outbreaks worldwide. In Greece, human salmonellosis is a mandatory notifiable disease, with laboratory surveillance being on a voluntary basis. This study aims to provide the first insights into the genetic characteristics and antimicrobial resistance profiles of 47 S. Enteritidis human isolates using whole-genome sequencing (WGS) technology. The S. Enteritidis population was mainly resistant to fluoroquinolones due to gyrA point mutations, whereas one isolate presented a multi-resistant plasmid-mediated phenotype. ST11 was the most frequent sequence type, and phylogenetic analysis through the cgMLST and SNP methods revealed considerable genetic diversity. Regarding virulence factors, 8 out of the 24 known SPIs and C63PI were detected. Due to the observed variability between countries, it is of utmost importance to record the circulating S. Enteritidis strains' structure and genomic epidemiology at the national level. WGS is a valuable tool that is revolutionizing our approach to Salmonella by providing a deeper understanding of these pathogens and their impact on human health.

Rapid and Sensitive Detection of Shiga Toxin-Producing Escherichia coli (STEC) from Food Matrices Using the CANARY Biosensor Assay.

Shiga toxin-producing Escherichia coli (STEC) causes a wide spectrum of diseases including hemorrhagic colitis and hemolytic uremic syndrome (HUS). Previously, we developed a rapid, sensitive, and potentially portable assay that identified STEC by detecting Shiga toxin (Stx) using a B-cell based biosensor platform. We applied this assay to detect Stx2 present in food samples that have been implicated in previous STEC foodborne outbreaks (milk, lettuce, and beef). The STEC enrichment medium, modified Tryptone Soy Broth (mTSB), inhibited the biosensor assay, but dilution with the assay buffer relieved this effect. Results with Stx2a toxoid-spiked food samples indicated an estimated limit of detection (LOD) of ≈4 ng/mL. When this assay was applied to food samples inoculated with STEC, it was able to detect 0.4 CFU/g or 0.4 CFU/mL of STEC at 16 h post incubation (hpi) in an enrichment medium containing mitomycin C. Importantly, this assay was even able to detect STEC strains that were high expressors of Stx2 at 8 hpi. These results indicate that the STEC CANARY biosensor assay is a rapid and sensitive assay applicable for detection of STEC contamination in food with minimal sample processing that can complement the current Food Safety Inspection Service (US) methodologies for STEC.

Salmonella spp. in Domestic Ruminants, Evaluation of Antimicrobial Resistance Based on the One Health Approach-A Systematic Review and Meta-Analysis.

Salmonella spp. pose a global threat as a leading cause of foodborne illnesses, particularly prevalent in the European Union (EU), where it remains the second cause of foodborne outbreaks. The emergence of antimicrobial resistance (AMR) in Salmonella spp. has become a critical concern, complicating treatment strategies and escalating the risk of severe infections. The study focuses on large and small ruminants, identifying a prevalence of Salmonella spp. in slaughterhouses and revealing varied AMR rates across antimicrobial families throughout a meta-analysis. Also, comparison with AMR in human medicine was carried out by a systematic review. The results of the present meta-analysis displayed a prevalence of Salmonella spp. in large and small ruminants at slaughterhouses of 8.01% (8.31%, cattle; 7.04%, goats; 6.12%, sheep). According to the AMR of Salmonella spp., 20, 14, and 13 out of 62 antimicrobials studied were classified as low (<5%), high (>5% but <10%), and very high (>10%), respectively. Salmonella spp. did not display AMR against aztreonam, mezlocillin, ertapenem, meropenem, cefoxitin, ceftazidime, levofloxacin, tilmicosin, linezolid, fosfomycin, furazolidone, quinupristin, trimethoprim and spectinomycin. In contrast, a prevalence of 100% of AMR has been described against ofloxacin, lincomycin, and cloxacillin. In the context of the main antibiotics used in the treatment of human salmonellosis, azithromycin was shown to have the highest resistance among Salmonella spp. isolates from humans. Regarding cephalosporins, which are also used for the treatment of salmonellosis in humans, the prevalence of Salmonella spp. resistance to this class of antibiotics was similar in both human and animal samples. Concerning quinolones, despite a heightened resistance profile in Salmonella spp. isolates from ruminant samples, there appears to be no discernible compromise to the efficacy of salmonellosis treatment in humans since lower prevalences of AMR in Salmonella spp. isolated from human specimens were observed. Although the resistance of Salmonella spp. indicates some degree of concern, most antibiotics are not used in veterinary medicine. Thus, the contribution of cattle, sheep and goats to the rise of antibiotic resistance of Salmonella spp. and its potential impact on public health appears to be relatively insignificant, due to their low prevalence in carcasses and organs. Nevertheless, the observed low prevalence of Salmonella spp. in ruminants at slaughterhouse and the correspondingly low AMR rates of Salmonella spp. to key antibiotics employed in human medicine do not indicate that ruminant livestock poses a substantial public health risk concerning the transmission of AMR. Thus, the results observed in both the meta-analysis and systematic review suggests that AMR is not solely attributed to veterinary antibiotic use but is also influenced by factors such as animal health management (i.e., biosecurity measures, prophylactic schemes) and human medicine.

Comparative genomics of Cryptosporidium parvum reveals the emergence of an outbreak-associated population in Europe and its spread to the United States.

The zoonotic parasite Cryptosporidium parvum is a global cause of gastrointestinal disease in humans and ruminants. Sequence analysis of the highly polymorphic gp60 gene enabled the classification of C. parvum isolates into multiple groups (e.g., IIa, IIc, Id) and a large number of subtypes. In Europe, subtype IIaA15G2R1 is largely predominant and has been associated with many water- and food-borne outbreaks. In this study, we generated new whole-genome sequence (WGS) data from 123 human- and ruminant-derived isolates collected in 13 European countries and included other available WGS data from Europe, Egypt, China, and the United States (n = 72) in the largest comparative genomics study to date. We applied rigorous filters to exclude mixed infections and analyzed a data set from 141 isolates from the zoonotic groups IIa (n = 119) and IId (n = 22). Based on 28,047 high-quality, biallelic genomic SNPs, we identified three distinct and strongly supported populations: Isolates from China (IId) and Egypt (IIa and IId) formed population 1; a minority of European isolates (IIa and IId) formed population 2; and the majority of European (IIa, including all IIaA15G2R1 isolates) and all isolates from the United States (IIa) clustered in population 3. Based on analyses of the population structure, population genetics, and recombination, we show that population 3 has recently emerged and expanded throughout Europe to then, possibly from the United Kingdom, reach the United States, where it also expanded. The reason(s) for the successful spread of population 3 remain elusive, although genes under selective pressure uniquely in this population were identified.