Foodborne Disease Outbreaks Research Articles

Detection of Bacterial Pathogens in Ready-To-Eat Foods: Potential Public Health Hazard

The right to obtain safe food is one of the most vital and fundamental human rights that must not be compromised or neglected; this is important because foodborne diseases can lead to prolonged disability and even death. Our study examined 28 samples of ready-to-eat foods, of which 27 samples (96.4%), contained bacterial contaminants. The bacterial pathogens isolated include Escherichia coli (50%), Salmonella spp (75%) and Staphylococcus aureus (85.7%). All the samples of jollof rice (100%), bean porride (100%) and eba (100%) were contaminated while 85.7% of egusi soup samples contained bacterial contaminants. The presence of these bacterial pathogens in the ready-to-eat foods poses huge risk to public health. It calls for immediate and sustainable action to prevent the possibility of foodborne disease out-break and intoxication capable of harming public health and socio-economic development.

Characterization of a New and Efficient Polyvalent Phage Infecting E. coli O157:H7, Salmonella spp., and Shigella sonnei.

Ongoing outbreaks of foodborne diseases remain a significant public health concern. Lytic phages provide promising attributes as biocontrol agents. This study characterized KFS-EC3, a polyvalent and lytic phage, which was isolated from slaughterhouse sewage and purified by cesium chloride density centrifugation. Host range and efficiency of plating analyses revealed that KFS-EC3 is polyvalent and can efficiently infect E. coli O157:H7, Salmonella spp., and Shigella sonnei. KFS-EC3 had a latent time of 20 min and burst size of ~71 phages/infected cell. KFS-EC3 was stable and infectious following storage at a pH range of 3 to 11 and a temperature range of −70 °C to 60 °C. KFS-EC3 could inhibit E. coli O157:H7 growth by 2 logs up to 52 h even at the lowest MOI of 0.001. Genomic analysis of KFS-EC3 revealed that it consisted of 167,440 bp and 273 ORFs identified as functional genes, without any genes associated with antibiotic resistance, virulence, allergenicity, and lysogenicity. This phage was finally classified into the Tequatrovirus genus of the Myoviridae family. In conclusion, KFS-EC3 could simultaneously infect E. coli O157:H7, S. sonnei, and Salmonella spp. with the lowest MOI values over long periods, suggesting its suitability for simultaneous pathogen control in foods.

Two foodborne disease outbreaks caused by Salmonella putten

Objective To retrospectively analyze 2 foodborne disease outbreaks caused by Salmonella putten in Hefei, and we explore the relationship and causes of the 2 outbreaks, so as to provide scientific basis for the prevention and treatment of similar outbreaks in the future. Methods Field epidemiological surveys were conducted on the patients found in the outbreaks, hygienic surveys were conducted in the places where the outbreaks happened, the results were analyzed by descriptive analysis, specimens of surplus food, suspicious food and anal swabs of patients were collected for microbiological testing, the homology of strains was analyzed by pulsed-field gel electrophoresis (PFGE). Results Five cases were found in the outbreak A, and 6 cases were found in the outbreak B, all cases had eaten a same brand of braised chicken in the outbreak, the main clinical manifestations were diarrhea, fever, headache, nausea, some patients had abdominal pain and vomiting; the total viable counts of the same batch unopened food was 3.0×10 8 CFU/g, and the coliform counts was 3.5×10 7 CFU/g; The Salmonella putten was detected from 1 surplus food, 1 suspicious same batch unopened food, and 6 anal swabs of cases, which had homology by PFGE molecular typing analysis, there were 7 strains of the Salmonella putten, with a similar scale of 100%, and 1 strain of another suspicious same batch unopened food, with a similar scale of 94.64%, with high homology. Conclusion Combined with field epidemiological surveys, hygienic surveys, clinical manifestations and microbiological testing results, the two events were foodborne disease outbreaks caused by the same Salmonella putten. 摘要： 目的 回顾性分析合肥市接连调査的两起普顿沙门菌引起的食源性疾病事件, 探讨两起事件发生的联系与 原因, 为今后预防和处置类似事件提供科学依据。 方法 对在事件发生地搜索到的患者进行现场流行病学调査, 事件 发生地开展现场卫生学调査, 调査结果采用描述性分析; 采集剩余食品、可疑食品及病例肛拭子标本进行微生物学检 验, 运用脉冲场凝胶电泳(PFGE), 分析菌株的同源性。 结果 A事件发现5例病例, B事件发现6例病例, 所有病例均曾 在事件中食用过某同一品牌烧鸡, 主要临床表现为腹泻、发热、头痛、恶心, 部分病例伴有腹痛、呕吐; 可疑食品同批次 未拆封食品中的菌落总数测定结果为3.0×10 8 CFU/g, 大肠菌群计数结果为3.5×10 7 CFU/g;在1份剩余食品、1份可疑食 品同批次未拆封食品、份病例肛拭子中均检出普顿沙门菌, 经PFGE分子分型分析, 7株普顿沙门菌分子分型图谱相似 度为100%, 另1份可疑食品同批次未拆封食品中检出的普顿沙门菌分子分型图谱与其余7株相似度为94.64%, 具有髙 度同源性。 结论 结合现场流行病学调査、现场卫生学调査、病例临床表现及实验室检验结果综合分析, 两起事件均 是由于患者食用了同一品牌变质烧鸡, 由同一种普顿沙门菌引起的食源性疾病事件。

Cascading effects of composts and cover crops on soil chemistry, bacterial communities and the survival of foodborne pathogens.

AimsRecent foodborne disease outbreaks have caused farmers to re‐evaluate their practices. In particular, concern that soil amendments could introduce foodborne pathogens onto farms and promote their survival in soils has led farmers to reduce or eliminate the application of animal‐based composts. However, organic amendments (such as composts and cover crops) could bolster food safety by increasing soil microbial diversity and activity, which can act as competitors or antagonists and reduce pathogen survival.Methods and ResultsLeveraging a study of a 27‐year experiment comparing organic and conventional soil management, we evaluate the impacts of composted poultry litter and cover crops on soil chemistry, bacterial communities and survival of Salmonella enterica and Listeria monocytogenes. We found that bacterial community composition strongly affected pathogen survival in soils. Specifically, organic soils managed with cover crops and composts hosted more macronutrients and bacterial communities that were better able to suppress Salmonella and Listeria. For example, after incubating soils for 10 days at 20°C, soils without composts retained fourfold to fivefold more Salmonella compared to compost‐amended soils. However, treatment effects dissipated as bacterial communities converged over the growing season.ConclusionsOur results suggest that composts and cover crops may be used to build healthy soils without increasing foodborne pathogen survival.Significance and Impact of the StudyOur work suggests that animal‐based composts do not promote pathogen survival and may even promote bacterial communities that suppress pathogens. Critically, proper composting techniques are known to reduce pathogen populations in biological soil amendments of animal origin, which can reduce the risks of introducing pathogens to farm fields in soil amendments. Thus, animal‐based composts and cover crops may be a safe alternative to conventional fertilizers, both because of the known benefits of composts for soil health and because it may be possible to apply amendments in such a way that food‐safety risks are mitigated rather than exacerbated.

Novel Outbreak-Associated Food Vehicles, United States.

Novel outbreak-associated food vehicles (i.e., foods not implicated in past outbreaks) can emerge as a result of evolving pathogens and changing consumption trends. To identify these foods, we examined data from the Centers for Disease Control and Prevention Foodborne Disease Outbreak Surveillance System and found 14,216 reported outbreaks with information on implicated foods. We compared foods implicated in outbreaks during 2007–2016 with those implicated in outbreaks during 1973–2006. We identified 28 novel food vehicles, of which the most common types were fish, nuts, fruits, and vegetables; one third were imported. Compared with other outbreaks, those associated with novel food vehicles were more likely to involve illnesses in multiple states and food recalls and were larger in terms of cases, hospitalizations, and deaths. Two thirds of novel foods did not require cooking after purchase. Prevention efforts targeting novel foods cannot rely solely on consumer education but require industry preventive measures.

Bimetallic Fe/Mn MOFs/MβCD/AuNPs stabilized on MWCNTs for developing a label-free DNA-based genosensing bio-assay applied in the determination of Salmonella typhimurium in milk samples

Monitoring of pathogenic bacteria plays a vital role in precluding foodborne disease outbreaks. In this research work, a genosensor based on innovative label-free DNA was developed for the detection of Salmonella. typhimurium (S. typhimurium) in the milk samples. To realize this objective, bimetallic Fe/Mn MOF is synthesized and mixed with methyl-β-cyclodextrin (MβCD) and AuNPs which are then stabilized on multi-walled carbon nanotubes (MWCNTs), and the obtained nanocomposite is immobilized on the Au electrode surface. Different characterization methods such as FE-SEM, TEM, EDS, FTIR, and XRD were used for investigating the particle size and morphological features. Electrochemical and impedimetric techniques were used for exploring the applicability of the fabricated genosensor. Under optimal circumstances, LOD and LOQ have acquired at 0.07 pM and 0.21 pM. Moreover, an extensive linear range of 1 pM−1 μM was resulted for ss-tDNA (single-stranded target DNA), R2 obtained 0.9991. The recoveries were obtained 95.6–104%. Great selectivity against one, two, and three-base mismatched sequences was also shown for fabricated biosensing assay. Furthermore, negative genosensing assay control for investigating selectivity was provided by the ss-tDNAs of Haemophilusinfluenzae and Shigella dysenteriae bacteria. Well-fabricated genosensing bio-assay represents better performance, great specificity, high sensitivity, increased active sites, and finally results in an increase in the electron transfer rate. It is to be noted that the organized genosensing bio-assay is capable of being re-used and re-generated in a straightforward manner to estimate the hybridization process.

Antibiotic Resistance and Plasmid Profile Analysis of Salmonella Enteritidis Isolated in Siberia and the Far East of Russia between 1990 and 2017.

Salmonella is one of the major causes of foodborne disease outbreaks globally. Specifically, Salmonella enterica subsp. enterica serovar Enteritidis (S. Enteritidis) is one of the major causes of zoonotic Salmonella infection in humans worldwide. In this study, we present data on antimicrobial resistance (AMR) and plasmid profiles of S. Enteritidis strains isolated from patients, food, and the environment in Siberia and the Far East of Russia obtained during Salmonella monitoring between 1990 and 2017. A total of 345 S. Enteritidis isolates were tested by the disk diffusion method with a set of 15 antibiotics using EUCAST breakpoints v. 10 and by plasmid profile analysis using the alkaline lysis method. The results have shown a substantial decrease in susceptibility to aminoglycosides and quinolones during the study period. No significant differences were found in the susceptibility of strains between regions as well as in the its correlation with different plasmid types of the pathogen. Several S. Enteritidis strains were found to be resistant to ampicillin, kanamycin, tetracycline, chloramphenicol, and cephalosporins. All tested S. Enteritidis strains were susceptible only to imipenem. In this study, we observed a relatively low level of AMR in S. Enteritidis strains isolated in Siberia and the Far East of Russia. Nevertheless, it is important to continue the molecular genetic monitoring and AMR surveillance of S. Enteritidis to track further increases in AMR using conventional phenotypic susceptibility testing and by introducing whole-genome sequencing to identify AMR mechanisms.

Validation of post-harvest antimicrobial interventions to control Shiga toxin-producing Escherichia coli (STEC) on market hog carcass surfaces

Although swine are less associated with STEC foodborne disease outbreaks, the potential for swine to serve as a source of STEC infections in human beings cannot be disregarded. This study compared eight USDA-approved antimicrobial intervention technologies to quantify their ability to reduce STEC contamination on market hog carcasses. Hogs were harvested to provide skin-on carcass sides, and eight sides (per three replications) were inoculated with a 7-strain STEC cocktail (ca. 5 log CFU/cm2 across all external and body cavity surfaces). Each side was randomly assigned to a final pre-chill wash treatment administered in a commercial Chad carcass cabinet using a low-volume spray [3% lactic acid (lLA; 130 °F), 400 ppm peracetic acid (lPAA), or acidified 400 ppm peracetic acid (laPAA)] or a high-volume wash [ambient water (hAW), 400 ppm PAA (hPAA), 400 or 600 ppm hypobromous acid (hDBDMH), or 71 °C water (hHW)] treatment according to a randomized complete block study design. Post-treatment (after a 10-min hanging drip) and post-chilling (18 h at 2 °C) STEC reductions were compared for external skin-on surfaces and internal body cavity lean surface tissue. Post-treatment color changes were determined for lean, adipose, and skin carcass surfaces before and after chilling. When applied to the external, skin-on surface, the hHW, hPAA, and hDBDMH600 deluge washes were significantly (P ≤ 0.05) more effective than the other intervention technologies, achieving STEC reductions of 3.8, 3.4, and 3.2 log CFU/cm2, respectively. In comparison, the hAW control reduced STEC by 1.7-log CFU/cm2 on the external, skin-on surface. The carcass interventions were less effective at reducing STEC populations attached to interior body cavity (diaphragm region), with post-chill populations reduced by 0.9–2.2 log cycles, while the hAW control wash achieved a 0.6-log reduction. None of the treatments negatively impacted instrumental carcass color. While all market hog carcass interventions reduced STEC populations, larger reductions were observed when applied to the external, skin-on surface, with the largest reductions achieved by the hHW, hPAA, and hDBDMH600 deluge washes. These data equip pork processors with the information necessary to support decision-making when selecting an intervention technology.

Towards improving food safety in Cambodia: Current status and emerging opportunities

Cambodia has made significant efforts to improve nutritional outcomes while demonstrating increasing interest in ensuring that food safety challenges do not negate these efforts. This integrative review examines food safety in Cambodia to identify areas where efforts, both existing and recommended, could focus to best limit Cambodians’ exposure to foodborne disease. The review considers: 1) documented foodborne disease outbreaks in Cambodia; 2) aggregated food safety research taking place in Cambodia; 3) current food safety regulatory structures in the country; and 4) gaps in food safety knowledge or practices. Lastly, the review proposes an framework to bridge food safety gaps through the integration of improved surveillance, targeted intervention research informed, and a comprehensive understanding of Cambodians motivations, opportunities, and capabilities to adopt food safety practices.

Nanopore-Based Surveillance of Zoonotic Bacterial Pathogens in Farm-Dwelling Peridomestic Rodents.

The effective control of rodent populations on farms is crucial for food safety, as rodents are reservoirs and vectors for several zoonotic pathogens. Clear links have been identified between rodents and farm-level outbreaks of pathogens throughout Europe and Asia; however, comparatively little research has been devoted to studying the rodent–agricultural interface in the USA. Here, we address this knowledge gap by metabarcoding bacterial communities of rodent pests collected from Minnesota and Wisconsin food animal farms. We leveraged the Oxford Nanopore MinION sequencer to provide a rapid real-time survey of putative zoonotic foodborne pathogens, among others. Rodents were live trapped (n = 90) from three dairy and mixed animal farms. DNA extraction was performed on 63 rodent colons along with 2 shrew colons included as outgroups in the study. Full-length 16S amplicon sequencing was performed. Our farm-level rodent-metabarcoding data indicate the presence of multiple foodborne pathogens, including Salmonella spp., Campylobacter spp., Staphylococcus aureus, and Clostridium spp., along with many mastitis pathogens circulating within five rodent species (Microtus pennsylvanicus, Mus musculus, Peromyscus leucopus, Peromyscus maniculatus, and Rattus norvegicus) and a shrew (Blarina brevicauda). Interestingly, we observed a higher abundance of enteric pathogens (e.g., Salmonella) in shrew feces compared to the rodents analyzed in our study. Knowledge gained from our research efforts will directly inform and improve farm-level biosecurity efforts and public health interventions to reduce future outbreaks of foodborne and zoonotic disease.

Poly-l-lysine-functionalized magnetic beads combined with polymerase chain reaction for the detection of Staphylococcus aureus and Escherichia coli O157:H7 in milk

Rapid and credible detection of pathogens is essential to prevent and control outbreaks of foodborne diseases. In this study, a poly-l-lysine-functionalized magnetic beads (PLL-MB) strategy combined with a PCR assay was established to detect Staphylococcus aureus. We also detected Escherichia coli O157:H7 to further verify the strategy for gram-negative bacteria detection. Poly-l-lysine has strong positive charges because of its amino groups, which can conjugate with the carboxyl of carboxyl magnetic beads. Furthermore, it can be used to combine with bacteria through electrostatic adsorption. Under optimum conditions, the developed PLL-MB complexes showed 90% capture efficiency in phosphate-buffered saline and 85% capture efficiency in milk for S. aureus detection. The limit of detection of the PLL-MB-PCR assay was 102 cfu/mL (1.8 × 102 cfu/mL for S. aureus and 7 × 102 cfu/mL for E. coli O157:H7) in phosphate-buffered saline and milk samples. The whole assay can be performed within 4 h. The proposed strategy showed a lower limit of detection when compared with the conventional PCR assay without enrichment. In addition, this method exhibited the advantages of a high-efficient, cost-efficient, and simple operation, indicating its potential applications in foodborne pathogen detection.

Inconsistent PCR detection of Shiga toxin-producing Escherichia coli: Insights from whole genome sequence analyses.

Shiga toxin-producing Escherichia coli (STEC) have been linked to food-borne disease outbreaks. As PCR is routinely used to screen foods for STEC, it is important that factors leading to inconsistent detection of STEC by PCR are understood. This study used whole genome sequencing (WGS) to investigate causes of inconsistent PCR detection of stx1, stx2, and serogroup-specific genes. Fifty strains isolated from Alberta feedlot cattle from three different studies were selected with inconsistent or consistent detection of stx and serogroup by PCR. All isolates were initially classified as STEC by PCR. Sequencing was performed using Illumina MiSeq® with sample library by Nextera XT. Virtual PCRs were performed using Geneious and bacteriophage content was determined using PHASTER. Sequencing coverage ranged from 47 to 102x, averaging 74x, with sequences deposited in the NCBI database. Eleven strains were confirmed by WGS as STEC having complete stxA and stxB subunits. However, truncated stx fragments occurred in twenty-two other isolates, some having multiple stx fragments in the genome. Isolates with complete stx by WGS had consistent stx1 and stx2 detection by PCR, although one also having a stx2 fragment had inconsistent stx2 PCR. For all STEC and 18/39 non-STEC, serogroups determined by PCR agreed with those determined by WGS. An additional three WGS serotypes were inconclusive and two isolates were Citrobacter spp. Results demonstrate that stx fragments associated with stx-carrying bacteriophages in the E. coli genome may contribute to inconsistent detection of stx1 and stx2 by PCR. Fourteen isolates had integrated stx bacteriophage but lacked complete or fragmentary stx possibly due to partial bacteriophage excision after sub-cultivation or other unclear mechanisms. The majority of STEC isolates (7/11) did not have identifiable bacteriophage DNA in the contig(s) where stx was located, likely increasing the stability of stx in the bacterial genome and its detection by PCR.

Food Safety Characterization of Food Enterprises for Inclusive Nutrition Sensitive Value Chain Development in Sub-Saharan Africa. A Case Study of the Orange Fleshed Sweet Potato Value Chain in Kenya

Food safety receives minimal attention and only captures national attention during foodborne disease outbreaks. The objective of this study was to explore the knowledge, attitudes and practices on food safety aspects related to Orange Fleshed Sweet potato (OFSP) along the food value chain in Kenya. A cross-sectional study was designed and investigated food safety knowledge, attitudes and practices (KAP) among the OFSP processors, traders, and consumers of street foods in Kenya. A socio-demographic questionnaire and KAP questionnaire were used as data collection instruments. The study included OFSP traders OFSP puree processors, large retailer’s bakeries and consumers in Nairobi. The OFSP traders included were the suppliers of OFSP in the markets around Nairobi city. The OFSP consumers included the people who buy cooked OFSP from the street vendors in Nairobi city. Descriptive statistics such as percentage means and standard deviation were used to summarize the socio-demographic data and the knowledge, attitude, practices, and overall KAP. Pearson’s correlation was used to establish an association of the three study components. Adjusted linear regression was used to assess the effect of food safety on knowledge, attitude, and practices. Knowledgeable, positive attitude and good practice on food safety were considered for mean scores above 80%. Statistical significance was set at p < 0.05 . The findings from the OFSP processors revealed a mean percentage score for knowledge, attitude, practices at 70.7%, 93.5%, and 90%, respectively, with an overall mean score of 84.6%. Lower education level was statistically significantly associated with food safety practices at p = 0.002. Adjusted linear regression found a significant effect of food safety on knowledge at p<0.001. Adjusted multiple regression revealed that age was statistically significantly associated with food safety knowledge, and food safety attitude (both at p <0.001). Education level was significantly associated with food safety practices (p<0.001). Findings from OFSP traders revealed mean percentage scores for knowledge, attitude, practices at 63.1%, 74.4%, and 64.7%, respectively, with an overall mean score of 67.4%. Pearson’s correlation analysis revealed a strong positive correlation between food safety attitude and food safety practice p= 0.015. Similarly, a strong positive correlation between food safety practice and food safety knowledge was noted (p <0.001). Adjusted linear regression found that Food safety practice was significantly impacted by both knowledge and attitude R2=0.578 F=49.6 p=0.000. Results from OFSP consumers revealed mean percentage scores for knowledge, attitude, practices at 66.2%, 87.3%, and 91.6%, respectively with an overall mean score of 81.7%. Lower education level was statistically significantly associated with inappropriate practices among OFSP consumers p = 0.040. Pearson’s correlation analysis revealed a week positive correlation between food safety knowledge attitude and practice. : This study reveals a gap in the area of food safety knowledge, attitude, and practice along the OFSP value chain. The study highlights the need for policymakers to address and review the knowledge, attitude, and practices in the food industry, to raise food safety awareness campaigns and organize more targeted training along the food chains to reduce the foodborne disease burden. Keywords: Food safety, Knowledge, attitude, practices, processor, traders, consumers DOI: 10.7176/FSQM/110-05 Publication date: September 30 th 2021

Investigation and analysis of foodborne disease outbreak in a school caused by Samonella enteritidis

Investigation and analysis of foodborne disease outbreak in a school caused by Samonella enteritidis

Escherichia coli Specific Virulence-Gene Markers Analysis for Quality Control of Ovine Cheese in Slovakia.

Shiga toxin-producing and extra-intestinal pathogenic Escherichia coli (E. coli) have the potential to spread through faecal waste, resulting in contamination of food and causing foodborne disease outbreaks. With the aim of characterizing unpasteurized ovine cheese in Slovakia, a total of 92 E. coli strains were examined for eleven representative virulence genes typical for (extra-)intestinal pathogenic E. coli and phylogenetic grouping. Phylogenetic groups B1 (36%) and A (32%) were the most dominant, followed by groups C (14%) and D (13%), while the lowest incidence was recorded for F (4%), and E (1%), and 43 (47%) samples carried at least one virulent gene, i.e., potential pathogens. Isolates present in groups E, F and D showed higher presence of virulence genes (100%, 75%, and 67%), versus 55%, 39%, and 28% in commensal B1, C, and A, respectively. Occurrence of papC and fyuA (both 24%) was highest, followed by tsh, iss, stx2, cnf1, kpsII, cvaC, stx1, iutA and eaeA. Nine E. coli strains (almost 10% of all tested and around 21% of our virulence-gene-associated isolates) harboured stx1, stx2 or eae. Ovine cheeses in Slovakia are highly contaminated with E. coli including potentially pathogenic strains capable of causing intestinal and/or extra-intestinal diseases, and thus may pose a threat to public health while unpasteurized.

A lab-on-a-disc platform based on nickel nanowire net and smartphone imaging for rapid and automatic detection of foodborne bacteria

Foodborne pathogenic bacteria have been considered as a major risk factor for food safety. It is of great significance to carry out in-field screening of pathogenic bacteria to prevent the outbreaks of foodborne diseases. In this study, a portable lab-on-a-disc platform with a microfluidic disc was developed for rapid and automatic detection of Salmonella typhimurium using a nickel nanowire (NiNW) net for effective separation of target bacteria, horseradish peroxidase nanoflowers (HRP NFs) for efficient amplification of biological signals, and a self-developed smartphone APP for accurate analysis of colorimetric images. First, the microfluidic disc was preloaded with reagents and samples and centrifuged to form one bacterial sample column, one immune NiNW column, one HRP NF column, two washing buffer columns and one tetramethylbenzidine (TMB) column, which were separated by air gaps. Then, a rotatable magnetic field was specifically developed to assemble the NiNWs into a net, which was automatically controlled by a stepped motor to successively pass through the sample column for specific capture of target bacteria, the HRP NF column for specific label of target bacteria, the washing columns for effective removal of sample background and non-specific binding NFs, and the TMB column for colorimetric determination of target bacteria. The color change of TMB from colorless to blue was finally analyzed using the smartphone APP to quantitatively determine the target bacteria. This lab-on-a-disc platform could detect Salmonella typhimurium from 5.6 × 101 CFU/20 µL to 5.6 × 105 CFU/20 µL in 1 h with a lower detection limit of 56 CFU/20 µL. The recovery of target bacteria in spiked chicken samples ranged from 97.5% to 101.8%. This portable platform integrating separation, labeling, washing, catalysis and detection onto a single disc is featured with automatic operation, fast reaction, and small size and has shown its potential for in-field detection of foodborne pathogens.

Analysis of foodborne diseases outbreaks in schools from 2011 to 2020 in Henan Province

Objective To analyze the epidemiological characteristics of school foodborne disease outbreaks in Henan Province from 2011 to 2020 and to provide the basis for effective prevention and control of school foodborne disease outbreaks. Methods The outbreaks of foodborne diseases in schools in Henan Province reported by the foodborne disease outbreak surveillance system from 2011 to 2020 were statistically analyzed. Results A total of 47 outbreaks of school foodborne diseases were reported in Henan province in the past 10 years, with a total of 1 258 cases, 701 hospitalizations and 1 death. Zhengzhou, Zhumadian, Xinyang and Xinxiang were the top 4 cities in Henan Province in terms of the number of school foodborne disease outbreaks reported. The peak of foodborne illness incidents in schools was in June and September. The largest number of incidents occurred in middle school canteens and primary school canteens (all 12). The number of reported incidents (12) and the number of cases of foodborne diseases (371) in schools caused by cereals and their products were the largest. Pathogenic bacteria and their toxins were the main pathogenic factors that caused the outbreaks of foodborne diseases in schools, accounting for 78.26% of the identified causes. Bacillus cereus was the top pathogens causing foodborne diseases outbreaks in schools. The pathogenic factor that caused the largest number of cases was Diarrheogenic Escherichia Coli, and the pathogenic factor that caused the death cases was poisonous mushrooms. Apart from unexplained incidents, improper processing was the main link leading to foodborne diseases outbreaks in schools. Conclusion The primary and middle school students are the group with high incidence of foodborne diseases in schools. The supervision and management of school canteen should be strengthened in summer to prevent the outbreak of bacterial foodborne diseases caused by improper processing and storage of grain food. 【摘要】 目的 分析河南省 2011—2020 年学校食源性疾病暴发事件的流行病学规律及特点, 为有效防控学校食源性疾病 暴发事件提供依据。 方法 对国家食品安全风险评估中心的食源性疾病暴发监测系统报告的 2011—2020 年河南省学校 食源性疾病暴发事件进行流行病学统计分析。 结果 河南省 10 年间共报告学校食源性疾病暴发事件 47 起, 累计发病人 数 1 258 人, 住院人数 701 人, 死亡 1 人。河南省学校食源性疾病暴发事件报告起数前 4 位的城市为郑州市、驻马店市、信 阳市, 新乡市。学校食源性疾病事件高峰期是 6 和 9 月。中学食堂和小学食堂导致的事件数最多 (均为 12 起)。粮食制品 引起的学校食源性疾病上报事件数和发病人数最多 (14 起, 371 人)。致病菌及其毒素是引起学校食源性疾病暴发事件的 主要病原因子, 占查明原因事件数的 78.26%。引起学校食源性疾病暴发事件最多的致病菌是蜡样芽孢杆菌, 引起发病人 数最多的致病因素是致泻大肠埃希菌, 引发死亡病例的致病因素是毒蘑菇。除原因不明的事件外, 加工不当是导致学校食 源性疾病暴发事件的主要环节。 结论 中小学生是学校食源性疾病高发群体, 应加强夏秋季学校食堂的监督和管理, 预防 粮食类食品加工储存不当导致的细菌性食源性疾病暴发事件。

Impacts of Microbial Food Safety in China and Beyond.

Impacts of Microbial Food Safety in China and Beyond.

Microbiological survey and occurrence of bacterial foodborne pathogens in raw and ready-to-eat green leafy vegetables marketed in Tehran, Iran.

Fresh leafy (FL) and ready-to-eat (RTE) vegetables are recognized as an important source of foodborne disease outbreaks worldwide. Currently, there are no data available for the prevalnce of bacterial foodborne pathogens (FBPs) in raw vegetables consumed in Iran. Here, we evalated the presence of common bacterial FBPs among 366 samples of raw vegetables including 274 FL and 92 RTE collected from 21 districts of Tehran. The presence of FBPs were screened using conventional microbiological culture methods and real-time PCR assays. Overall, a higher rate of bacterial contamination was detected in FL compared to RTE samples using both detection methods. The results obtained by microbiological methods showed that Staphylococcus aureus (134/366, 36.6%), followed by Escherichia coli (85/366, 23.2%) and Clostridium perfringens (66/366, 18%) were detetcted as the most prevalent pathogens in this study. Vibrio cholerae was not detected in any of the samples either by microbiological methods or by the real-time PCR assays. There was a noticeable reduction in the proportion of Campylobacter positive samples using conventional microbiological methods (3.5%) compared to the real-time PCR assay (20.7%). The proportion of FL and RTE positive samples obtained by conventional microbiological methods was significantly different (P<0.05) for C. perfringens, Campylobacter spp. and S. aureus. The proportion of positive samples in FL and RTE vegetables obtained by the real-time PCR assays was significantly different (P<0.05) for C. perfringens, S. aureus, Helicobacter pylori and STEC/EHEC, the last one was found more frequently in RTE than in FL samples. Our findings indicated a contamination of FL and RTE vegetables in Iran with a range of well-known and emerging FBPs. Positivity and the distribution of bacterial species from the current data indicated different contamination sources, and overall a lack of effective decontamination steps during the production chain. Moreover, further information about the quality of the water, the hygiene measures implemented during the processing, storage and marketing are required to better identify the critical points and define the proper measures.

Policy responses to foodborne disease outbreaks in the United States and Germany

This paper explores differences in national responses to foodborne disease outbreaks, addressing both the sources of policy divergence and their implications for public health and coordinated emergency response. It presents findings from a comparative study of two multi-state E. coli outbreaks, one in the United States (2006) and one in Germany (2011), demonstrating important differences in how risk managers understood and responded to each nation’s first major outbreak associated with fresh produce. Drawing on a qualitative analysis of 36 semi-structured interviews with key stakeholders and hundreds of archival documents, this paper traces how social constructions of the E. coli risk interacted with organizational dynamics among state and industry actors to produce divergent policy outcomes: the U.S. outbreak was understood primarily as an agricultural problem that led to an industry-led agricultural solution, whereas the German outbreak was understood as a human disease problem that did not result in a substantial policy response once the acute health crisis passed. The paper concludes by discussing how these policy processes generate partial solutions to foodborne contamination that expose modern societies to systemic vulnerabilities.