Abstract:Objective To characterize the molecular epidemiology of Campylobacter jejuni （C. jejuni） infections in foodborne diarreal cases in Baoshan District， Shanghai， and to explore the genetic evolutionary relationships among C. jejuni isolates.Methods Statistical and genomic analyses were performed on 68 C. jejuni isolates obtained from diarrheal cases at intestinal outpatient clinics in Baoshan District between 2023 and 2024. Based on whole-genome sequencing data， multilocus sequence typing （MLST）， clonal complex （CC） analysis， heatstable serotyping （HS）， and core-genome single-nucleotide polymorphism （SNP） phylogenetic analysis were conducted.Results The detection rate of C. jejuni was higher in spring and summer， with meat and meat products identified as the suspected food vehicles. A total of 46 sequence types （STs） were identified， which clustered into 16 clonal complexes （CCs）. The most prevalent CC was CC464， followed by CC574， and CC45. The predominant HS types were HS2， HS8/17， and HS5/31. Core-genome analysis revealed four pairs of isolates ≤5 SNP differences， and epidemiological investigation demonstrated a high degree of relatedness among these strains.Conclusion C. jejuni infections in the local population exhibit a higher detection rate in spring and summer， with meat and meat products as the primary suspected sources. Molecular epidemiology of these isolates shows a polyclonal distribution with evidence of short-chain transmission events. Integrating genomic sequencing into routine surveillance for rapid typing and cluster identification facilitates timely traceability and supports precise prevention and control of foodborne diseases.

Abstract:Objective To investigate the contamination status of foodborne pathogens and the microbial community structure in the whole industry chain of lettuce production in Wuhan City and Jingzhou City， Hubei Province， so as to provide fundamental data for food safety risk assessment.Methods In 2022， planting bases with production entities were selected， along with their downstream vegetable processing， distribution， and catering enterprises. Samples were collected on a quarterly basis throughout the entire monitoring process. The contamination status of Listeria monocytogenes， Salmonella， and diarrheagenic Escherichia coli were detected according to National Food Safety Standards. Metagenomic sequencing was used to analyze the microbial community structure and diversity during lettuce growth.Results A total of 263 samples were collected from the whole process monitoring of lettuce planting and production， from which only one sample was detected positive for Salmonella. Twenty-three samples were subjected to metagenomic sequencing. At the kingdom level， Bacteria， Fungi， Archaea， and Eukaryota were annotated. At the phylum level， the core dominant groups of bacteria were Pseudomonadota and Actinomycetota. At the genus level， Streptomyces and Pseudomonas were dominant. Both dimensionality reduction analysis based on species abundance and distance-based sample clustering analysis revealed consistent microbial community structures within groups but significant differences between groups.Conclusion The contamination rate of foodborne pathogens in lettuce planting and production process in Hubei Province is relatively low. Soil， irrigation water， and organic fertilizer exhibit high microbial abundance and diversity， indicating the presence of mature ecosystems.

Abstract:Objective To establish an analytical method for the rapid determination of 5 microcystins （MCs） in aquatic products using dispersive solid phase extraction combined with ultra performance liquid chromatography-tandem mass spectrometry， and to determine the MCs in 106 aquatic product samples from Anhui Province.Methods After extraction and purification on aquatic samples， the separation of 5 MCs was achieved on a column under gradient elution conditions with 0.1% formic acid water and acetonitrile as the mobile phases. The measurements were performed using positive electrospray ionization mode under multiple reaction monitoring with segmented scanning. A total of 106 samples of fishes， shrimps， and bivalve shellfishes were collected from Anhui Province and analyzed using the established method.Results The 5 MCs exhibited good linearity in the concentration range of 0.01-10.0 μg/L， with linear correlation coefficients ranging from 0.998 5 to 0.999 9. The detection limits were between 0.05 and 0.25 μg/kg， and the quantification limits were between 0.1 and 0.5 μg/kg. The spiked average recoveries at three levels （low， medium， and high） ranged from 67.0% to 113.0%， with the relative standard deviations （n=6） below 11.4%. Among 106 aquatic product samples from Anhui Province， 4 MCs， namely MC-LR， MC-RR， MC-YR and MC-LF were detected. Among these， MC-LR exhibited the highest detection rate （15.1%）， with detected concentrations ranging from 2.62 to 117.00 μg/kg.Conclusion This method features simple pretreatment， excellent purification efficiency， high sensitivity and accuracy. it enables rapid determination of various microcystins in a large number of aquatic products. The detection rate of MCs in shrimps and shellfishes is higher than that of fishes from Anhui Province. This study provides technical support for the quality and safety supervision of aquatic products and rapid identification of potential hazards.

Abstract:Objective To establish a duplex real-time fluorescent quantitative PCR method for simultaneous and rapid detection of Cronobacter spp. and Enterobacter cloacae （E. cloacae） in infant milk powder， and to provide technical support for microbial safety detection of infant milk powder.Methods While the specific primers and probes of E. cloacae used in this study were from other reports， the genus-specific primers and TaqMan probes of Cronobacter were newly designed. Different fluoresceins were used to label the two probes for Cronobacter spp. and E. cloacae， and also two specific amplification systems for these two bacteria were constructed. By optimizing components and amplification conditions of the reaction system， a duplex real-time fluorescence quantitative PCR method suitable for simultaneous detection of two target bacteria in infant milk powder was then established.Results The established duplex real-time fluorescent quantitative PCR method efficiently achieved simultaneous and specific detection of Cronobacter spp. and E. cloacae in infant milk powder in a single reaction system. The detection limit of Cronobacter plasmid was 1.63×10⁵ copies/mL， and the detection limit of E. cloacae plasmid was 1.64×10⁵ copies/mL. After enrichment culture， this method can effectively detect two target pathogens of 10 CFU/mL in milk powder samples.Conclusion The duplex real-time fluorescent quantitative PCR method is highly specific， rapid， and sensitive. It can efficiently realize the simultaneous screening of Cronobacter spp. and E. cloacae in infant milk powder. The developed method is straightforward， highly practical， and holds significant potential for routine applications， to ensure the microbial safety of infant milk powder.

Abstract:Objective To Establish a rapid method for the determination of seven biogenic amines （phenylethylamine， tyramine， putrescine， octopamine， cadaverine， tryptamine and histamine） in musalais wine based on an underivatized ultra-performance liquid chromatography-tandem mass spectrometry.Methods After solid-phase extraction， the samples were separated by gradient elution on an ACQUITY UPLC BEH Amide Column （2.1 mm×100 mm， 1.7 μm， 130 ?） using a mobile phase system of 0.3% formic acid water （10 mmol/L ammonium formate） solution and acetonitrile at a flow rate of 0.3 mL/min. Detection was performed using electrospray positive ionization and multiple reaction monitoring （MRM） mode， with quantification by the external standard method.Results Phenylethylamine， tyramine， putrescine， octopamine， cadaverine， and histamine exhibited good linearity within the concentration range of 5.0-500.0 μg/L， while tryptamine showed good linearity within the range of 10.0-500.0 μg/L. The correlation coefficients （R2） for the calibration curves of the seven biogenic amines were all greater than 0.98. The limits of detection ranged from 1.0 to 3.0 μg/L， and the limits of quantification ranged from 3.0 to 9.0 μg/L. The average spiked recoveries of biogenic amines in the Musalais wine matrix ranged from 75.59% to 109.89%， with relative standard deviations between 0.97% and 9.36%. Among 60 wine samples， putrescine， cadaverine， histamine， and tyramine were detected using the established method. The highest detection rate was observed for putrescine at 21.7%， followed by cadaverine （20.0%）， histamine （16.7%）， and tyramine （11.7%）. Combined contamination was present in the samples. Histamine had the highest average level at 5.532 0 mg/L.Conclusion This study establish a rapid， accurate， and stable method in detecting seven biogenic amines in musalais wine. The contamination status detected by this method in this study is consistent with other reports. Therefore， this study provides technical support for precise testing of biogenic amines from local specialty product musalais wine.

Abstract:Objective To investigate the status and challenges of allergen labeling on prepackaged snack foods in Qingdao City.Methods Totally 1 095 samples were randomly collected across nine major snack food categories. Allergen label information was then statistically analyzed using SPSS.Results The results showed an overall allergen labeling rate of 68.13% （746/1 095）， with only 23.74% （260/1 095） of products featuring preventive allergen labeling （PAL）. Notably， domestically produced foods exhibited a higher overall allergen labeling rate and a lower PAL rate than imported foods. Among the labeled products， 17.69% （132/746） included allergic foods beyond the “eight major categories”， while 14.61% （109/746） displayed allergen information in inconspicuous locations. Additionally， significant variability was observed in the presentation formats of allergen labels.Conclusion Although the allergen labeling rate for prepackaged snacks has improved considerably， the standardization of the allergen labeling remains inadequate， particularly for PAL， highlighting persistent regulatory shortcomings. To mitigate allergy risks and safeguard consumer health， standardizing allergen label formats， enhancing PAL-related regulations， and strengthening enforcement and oversight measures are recommended.

Abstract:Objective To investigate the prevalence of Fasciola spp. in cattle in Fujian Province， and to elucidate the composition and phylogenetic relationships of these species.Methods From May 2023 to May 2024， fecal samples were collected from cattle in eastern， western， southern， northern， and central region of Fujian Province in proportion to the regional cattle population. Fasciola eggs were collected using the sedimentation method and identified morphologically. The internal transcribed spacer 2 （ITS2） region of ribosomal DNA was amplified by PCR and sequenced. The obtained sequences were compared against the GenBank database， and a phylogenetic tree was constructed based on ITS2 sequences using MEGA software. Statistical analysis was performed using SPSS.Results The overall detection rate of Fasciola eggs was 21.9% （110/502）， with significant differences among the five regions （χ2=73.68， P<0.000 1）. The eggs were morphologically consistent. Size measurements of 160 eggs from 16 positive specimens correlated well with the sizes of Fasciola eggs. The results of ITS2 sequence alignment analysis for 9 PCR-positive specimens revealed that 4 ITS2 sequences showed 98.83%-99.60% similarity to the reference strain of Fasciola gigantica， while the remaining 5 ITS2 sequences showed 97.60%-99.80% similarity to the reference strain of Fasciola hepatica. Phylogenetic analysis indicated that the obtained ITS2 sequences clustered into two distinct branches with F. hepatica and F. gigantica， respectively.Conclusion The detection rates of Fasciola in cattle in Fujian are relatively high， and there is a co-endemic prevalence of F. hepatica and F. gigantica. Consumption of unwashed or undercooked aquatic plants poses a risk of Fasciola infection in humans.

Abstract:Objective To investigate the contamination levels of 11 mycotoxins such as aflatoxins in cereals and cereal products in Chongqing City， and to analyze the co- occurrence patterns of these mycotoxins， so as to provide basic data for the safety risk assessment， monitoring， and management of mycotoxins.Methods Using the monitoring data of mycotoxins levels in 358 cereal and cereal product samples in Chongqing City between 2016 and 2020， correlation cluster analysis and principal component analysis were adopted to analyze the correlations of the occurrence of multiple mycotoxins in different cereal and cereal product samples and the main contamination patterns.Results The contamination levels of the 11 mycotoxins were generally low across all samples. However， simultaneous contamination with multiple mycotoxins was observed in a high proportion of individual samples （5.31%-92.00%）. Corn and corn grits demonstrated significantly higher contamination levels of mycotoxins than paddy and rice， with 16.00% and 8.99% co-contaminated with six or more mycotoxins， respectively. Mycotoxins within the same class showed high inter-correlations and comparable contamination levels. Detection rate comparisons and principal component analysis indicated that Fusarium metabolites constitute the predominant contaminant category in cereals and cereal products.Conclusion Mixed mycotoxin contamination is prevalent in cereals and cereal products in Chongqing City， particularly in corn and corn products. Continuous monitoring is recommended， along with intensified field-based fungal prevention and control， and improved storage management during distribution， to reduce mycotoxin contamination levels in cereals and cereal products.

Abstract:Objective To explore the application of mixture models in the acute dietary exposure risk assessment of histamine.Methods Histamine concentrations in three typical food categories （marine fish， fermented meat products， and fermented bean products） were determined using liquid chromatography-tandem mass spectrometry （LC-MS/MS）. Finite mixture models （FMM） and extreme value mixture models （EVMM） were constructed and compared with the traditional lognormal distribution model to identify the optimal fitting models. Acute exposure risk assessments were subsequently conducted incorporating data from the 2018 Chinese National Food Consumption Survey.Results The optimal fitting models for the three typical food categories were Lognormal， Lognormal-GPD， and 2-Lognormal mixture models， respectively. At high contamination levels （P₉₉）， the relative errors for four types of foods estimated by the traditional Lognormal model were 24%， 86%， 191%， and 286%， whereas those estimated by the mixture models were significantly reduced to 4%， 3%， 5%， and 25%. Probabilistic acute exposure assessments based on the mixture models revealed that the mean histamine exposures among consumers of the three food categories were relatively low （0.234-0.852 mg/d）. The high-end exposures （P_99.9） were 20.609， 5.856， and 48.494 mg/d， respectively， all of which remained below the acute reference dose （ARfD） （50 mg/d）.Conclusion The acute health risks associated with histamine intake from the three typical food categories in the Chinese consumer population are within acceptable levels. In fitting the histamine concentrations across these three food categories， mixture models consistently outperform single-distribution models. Integrating mixture models into acute dietary exposure assessments can effectively mitigate the tail-fitting bias associated with complex contamination data， serving as a robust methodological supplement to conventional assessment models.

Abstract:Objective To investigate the public’s cognitive level， attitude inclination， consumption behavior， and key concerns regarding prepared dishes in China， and to provide a reference for policy and regulatory development， public education， and the high-quality development of the industry.Methods A questionnaire survey was conducted， and 574 valid responses were collected， which were analyzed in conjunction with three public opinion incidents related to prepared dishes.Results The public’s subjective awareness rate of prepared dishes was high （85.0%）， but the objective cognitive consistency rate was low （59.9%）， indicating a significant cognitive bias. The public generally recognized practical values such as convenience and timesaving， but had insufficient trust in safety and hygiene. They mainly focused on issues like raw material safety. Acceptance was higher for home cooking and take-out scenarios， but lower for canteens and restaurants. Public consumption behavior showed characteristics of high penetration but low frequency， with consumption purposes mainly influenced by age and income. Public opinion focused on differences in definition cognition， common industry problems， and the protection of the right to know.Conclusion It is recommended to make coordinated efforts in acknowledging cognitive differences， enhancing whole-chain supervision， promoting consumer-end disclosure， and fostering industrial upgrading， to establish a multi-stakeholder governance framework.

Abstract:Objective This study aimes to analyze the epidemiological characteristics of foodborne disease outbreaks in schools of Shanxi Province from 2011 to 2024， so as to provide scientific evidence for the formulation of targeted prevention and control strategies.Methods Relevant data of foodborne disease outbreaks during the 2011-2024 period were collected via the National Foodborne Disease Outbreak Surveillance System. Descriptive epidemiological methods were applied to analyze the distribution of incidents by time， region， location， causative foods， and pathogenic agents. Statistical approaches were used to analyze trends， seasonal distribution， and correlations.Results A total of 109 school-related foodborne disease outbreaks were reported in Shanxi Province from 2011 to 2024， involving 1 550 cases and 566 hospitalizations， with no deaths. The total number of outbreaks showed an upward trend between 2011 and 2017， followed by fluctuations after reaching the peak in 2017. High-incidence periods occurred in May， June， September， and November. Outbreaks were reported across all prefecture-level cities in the province， with the largest number recorded in middle schools and school canteens. Mixed foods， grains， and grain products， as well as meat and meat products were the predominant implicated foods. Improper food processing and storage were the leading causes. Pathogenic agents were identified in only 25.69% of the outbreaks， mainly including bacteria， toxic plants， and norovirus. A positive correlation was found between sampling rate and the detection rate of pathogenic agents.Conclusion School foodborne disease outbreaks in Shanxi Province exhibit distinct temporal， spatial， and institutional distribution characteristics， and improper food processing and storage serve as the major potential safety hazards. Targeted interventions corresponding to each risk point should be implemented to consolidate the main responsibility of food safety， strengthen whole-process supervision， improve the professional training of catering staff， and enhance emergency investigation capacity. These measures are essential to prevent and control the risk of foodborne diseases in schools.

Abstract:Objective To conduct on-site investigation of a foodborne disease outbreak， analyze the causes of the incident， and provide corresponding preventive and control measures.Methods A field epidemiological investigation， food hygiene investigation， and laboratory testing were carried out in response to a group gastroenteritis incident reported at a closed sports training center on 2^nd February 2024.Results The event identified a total of 15 cases， with an attack rate of 15.46% （15/97）. The main symptoms included abdominal pain （80%，12/15）， nausea （80%，12/15）， and vomiting （26.67%，4/15）， with a median incubation period of 35 minutes. A case-control study revealed that undercooked soybean milk was the causative food， and saponins were detected in the leftover soybean milk.Conclusion This incident is a foodborne disease outbreak caused by consumption of undercooked soybean milk. It exposes weaknesses in food safety supervision in collective dining facilities outside the education system. It is recommended that regulatory agencies incorporate such institutions into a routine regulatory framework with reference to school food safety management standards， and strengthen specialized inspections and health education during holiday periods.

Abstract:Poisonous mushroom poisoning is one of the important causes of foodborne disease outbreaks in China， serving as the leading cause of fatalities associated with foodborne diseases. In recent years， the incident ratio shows a rising tendency. Therefore， clarifying the epidemiological characteristics of poisonous mushroom poisoning is a necessary precondition for lowering the mortality ratio. This review retrieved and synthesized the research literature on mushroom poisoning epidemiology in China published over the past decade， with reported data as early as 2003. Comprehensive evidence were analyzed across four dimensions including temporal trends， geographic distribution， demographic patterns， and exposure settings. The limitations of existing research were also evaluated. Based on the findings， this review outlines prospects for future research and prevention strategies against poisonous mushroom poisoning.