Foodborne Disease Outbreaks Research Articles

Impact of Wastewater Use for Irrigation and Contamination of Lettuce by Enteric Viruses: Case of Ouagadougou Market Gardening Sites, Burkina Faso.

Raw vegetables irrigated with polluted water that may contain enteric viruses can be associated with foodborne viral disease outbreaks. The objective of this study is to investigate the possible transmission of enteric viruses from irrigation water to lettuce. Therefore, we performed a commercial multiplex real-time PCR assay to monitor the occurrence of enteric viruses in irrigation water samples and in raw vegetables that were cultivated at market gardening sites in Ouagadougou, Burkina Faso. Samples were collected from six market gardening sites located in Ouagadougou. RT-PCR was performed to detect norovirus GI, norovirus GII, rotavirus, enteric adenoviruses F (Serotype 40/41), astrovirus and sapovirus (Genogroups G1, 2, 4, 5). From the 10 irrigation water samples and the 80 lettuce samples, three (30%) and twenty-two (27.5%) were positive for enteric viruses, respectively. Norovirus GII, astrovirus and enteric adenoviruses F (Serotype 40/41) were the most frequently detected viruses in lettuce and irrigation water samples. Our results indicate that raw vegetables may be contaminated with a broad range of enteric viruses, which may originate from virus-contaminated irrigation water, and these vegetables may act as a potential vector of food-borne viral transmission.

Evaluating Foodborne Cyclosporiasis Using Foodborne Diseases Active Surveillance Network and Foodborne Disease Outbreak Surveillance System Data, 2015-2019.

Cyclosporiasis has been a nationally notifiable disease in the United States since 1999, and cases have increased in recent years. We evaluated characteristics of U.S. cases and outbreaks to identify gaps and potential prevention measures for mitigating cyclosporiasis. We assessed Cyclospora data from the Foodborne Diseases Active Surveillance Network (FoodNet) and from the Foodborne Disease Outbreak Surveillance System (FDOSS) collected between 2015 and 2019. There were 1,376 cyclosporiasis cases in FoodNet between 2015 and 2019. Approximately one-fifth (n = 290, 21.1%) reported recent international travel. Most cases occurred in 2018 (n = 334, 24.3%) and 2019 (n = 758, 55.1%). There was strong seasonality, with 1,160 (90.9%) cases in the summer months. Most travelers reported visiting Mexico (n = 182, 62.8%) and Guatemala (n = 25, 8.6%). Approximately two-thirds of FoodNet cases were outbreak associated (n = 987, 71.7%). Of the 79 outbreaks reported to FDOSS, 31 (39.2%) occurred in 2018 and 40 (50.6%) occurred in 2019. Outbreaks tended to occur in spring and summer months (n = 78, 98.7%), The most common age groups among the 2,335 cases with data available included 20-49 years (n = 1,168, 50.0%), 50-74 years (n = 985, 42.2%), and ≥75 years (n = 120, 5.1%). Although direct comparisons between FoodNet and FDOSS are not possible, both datasets indicate that the majority of Cyclospora transmission is domestic and not travel associated, as previously thought. These findings show the need for continued investment in Cyclospora research, including identifying populations that are underrepresented, or at higher risk for cyclosporiasis, and improved understanding of national sources and pathways of infection.

An outbreak of Clostridium perfringens infection on a training ship anchored in Busan, Korea.

In September 2023, an outbreak of food-borne disease occurred among students on a training ship docked in Busan. This was an epidemiological investigation with the aim of improving infection prevention activities and group meal service practices on board ships. In this study, a case was defined as an individual who experienced diarrhea more than twice a day during their training period aboard the training ship. A total of 171 exposed individuals including 6 food handlers was well-defined; therefore, a retrospective cohort study was conducted. We administered a questionnaire and conducted laboratory tests including 38 rectal swab samples. Relative risk (95% confidence interval) for each food item was calculated. Of the 165 students and school staff members, 41 met the case definition, resulting in an attack rate of 24.8%; all cases were students. The shape of the epidemic curve was unimodal, with the peak from 0:00 to 06:00 on September 7, 2023. Clostridium perfringens was detected in 9 cases, and no other pathogens were found. Significant relative risk was shown in 11 different food items. Clostridium perfringens was the causative pathogen of this outbreak on the training ship. Due to the lack of preserved food samples, the exact source of infection could not be confirmed. Ships are not classified as collective dining facilities, leaving them in a management blind spot. Therefore, specialized guidelines, voluntary inspections by the operating entities, and continuous education for managers and staff are necessary.

Whole genome sequencing assisted outbreak investigation of Salmonella enteritidis, at a hospital in South Africa, September 2022.

Health authorities were notified of a suspected outbreak of foodborne disease in a hospital in South Africa, where staff and patients reported acute onset of abdominal cramps, diarrhoea, fever and rigours after eating a chicken pasta meal. The aim of this report is to discuss the use of whole genome sequencing (WGS) analysis of bacterial isolates to support an epidemiological investigation. An epidemiological investigation led by the Infection Control Manager of the hospital and supported by an outbreak response team was conducted. Standard microbiological procedures were used to process stool samples and culture/identify diarrhoeal pathogens. Bacterial cultures were investigated using WGS performed using Illumina NextSeq technology, and WGS data were analysed using multiple bioinformatics tools, including those available at the Center for Genomic Epidemiology and EnteroBase. Core genome multilocus sequence typing (cgMLST) was used to investigate the phylogeny of isolates. Forty-nine cases were identified, with stool samples collected from 21 cases, and nontyphoidal Salmonella isolated from 19 out of 21 (90%) of the samples. All isolates were identified as Salmonella enterica serovar Enteritidis and differed from each other by ≤2 allele differences on cgMLST, indicating that isolates are highly genetically related. Delays in testing of food retention samples rendered the negative test results of limited value. A case-control study was conducted; eating chicken pasta was strongly associated with developing gastroenteritis (Odds Ration (OR) = 15.4, Chi-Square test with Yates correction p value = 0.02). The epidemiological evidence suggests that the chicken pasta was the likely vehicle of transmission in this outbreak, although the source of S. enterica serovar Enteritidis remains unknown.

Multiple antibiotic resistance of Salmonella Infantis in the Peruvian poultry production chain: Detection in birds, the farming environment, and chicken carcasses

Poultry can act as a reservoir of Salmonella enterica serotype Infantis (S. Infantis) of clinical and epidemiological importance because it triggers foodborne disease outbreaks and presents antibiotic multiresistance. The present study aimed to determine antimicrobial resistance in S. Infantis isolates from poultry livers, litter and chicken carcasses from Lima, Peru, during 2022–2023. S. Infantis was isolated from 10.1 % (27/267), 4.7 % (4/86), and 8 % (2/25) of the bird, litter and carcass samples, respectively. All isolates showed resistance to nalidixic acid (NA). In addition, 94 %, 76 %, 70 %, 48 %, and 45 % of the isolates showed resistance to tetracycline (TET), amoxicillin (AMX), chloramphenicol (C), gentamicin (GEN) and trimethoprim/sulfamethoxazole (TS), respectively. All isolates showed susceptibility to imipinem and amoxicillin/clavulanic acid. Of the isolates, 93.9 % displayed multidrug resistance. The most frequent resistance pattern was C-AMX-NA-GEN-TET (24.2 %, n=8), determined even from carcass isolates, followed by C-AMX-NA-TET (18.2 %, n=6), and C-AMX-NA-GEN-TS-TET (12.1 %, n=4). The presence of these multidrug-resistant S. Infantis isolates is a threat to food safety and public health.

Fresh produce-associated foodborne disease outbreaks in Australia, 2001 to 2017.

Fresh produce is an important source of foodborne outbreaks in Australia. Using descriptive analysis, we examined confirmed and suspected foodborne outbreaks associated with fresh produce in Australia recorded in the OzFoodNet outbreak register from 2001 to 2017. The outbreak register contains reports of foodborne disease outbreaks collected by OzFoodNet epidemiologists and public health officials. A fresh produce outbreak was defined as the occurrence of two or more cases of the same illness in which the investigation had implicated a common food and this food contained fresh produce. A total of 92 fresh produce outbreaks were reported, encompassing 3,422 reported illnesses, 446 hospitalisations and four deaths. Of these outbreaks, 76.1% (70/92) were caused by a known pathogen, with the majority caused by either Salmonella enterica (n = 30) or Norovirus (n = 29). Most outbreaks (77.2%; 71/92) were associated with consumption of foods containing multiple ingredients, some of which were not fresh produce. The largest outbreaks associated with a single fresh produce item included bean sprouts contaminated with S. enterica serovar Saintpaul (419 illnesses and 76 hospitalisations) and semi-dried tomatoes contaminated with Hepatitis A (372 illnesses and 169 hospitalisations). Restaurants (45.7%; n = 42/92) and commercial catering (15.2%: n = 14/92) were common settings for fresh produce outbreaks. Outbreaks occurred in all states and territories of Australia and in all seasons, with an increased frequency in the warmer months (September-May). Although the number of fresh produce-associated outbreaks did not seem to be increasing in Australia, integrated surveillance is needed to rapidly identify sources of infection due to the propensity of these outbreaks to be large and widespread.

Knowledge, attitude, and food safety practices among university students in Kilimanjaro region, northern Tanzania

Food safety is a public health concern worldwide due to an increased morbidity and mortality risk associated with the outbreak of food-borne diseases. This study aimed to assess knowledge, attitude, and food safety practices (KAP) among university students in northern Tanzania. This is interesting because it allows data to be collected for creating awareness on safety, sanitation, and quality of food available within and outside the university environments.We conducted a cross-sectional study among 407 university students in Kilimanjaro region and all authors participated equally. Participants completed an online, self-administered questionnaire. Data was analyzed using SPSS version 25 and summarized using descriptive statistics. The Chi-squared test compared the proportion of KAP by participant characteristics and the multiple logistic regression model used to determine the associated factors. Participants had a mean age (standard deviation) of 23.2 (2.6) years, 51.4% were males, and 83% were < 25 years. The overall proportion of good knowledge, attitude, and food safety practices were 82.6, 78.4, and 31.9%, respectively. Higher odds of knowledge and attitude on food safety were students from KCMUCo (OR = 2.36; 95% CI 1.33–4.17) and (OR = 4.80; 95% CI 2.67–8.63). Also higher odds of food safety practice were students with good knowledge (OR = 1.80; 95% CI 1.03–3.13).Good food safety knowledge but not attitudes was associated with good food safety practices. This shows the need to introduce practical food safety within college environments to help students improve food hygiene and safety practices.

Essential oils application as Bacillus cereus antispore agent in food hygiene

Adherence of Bacillus cereus spores to dairy industry equipment is a serious problem, causing food spoilage and, occasionally, outbreaks of foodborne diseases. Antimicrobial essential oils (EOs) have been proposed as an alternative to synthetic disinfectants due to their environmentally friendly properties. The aim of this study was to assess the effect of Cymbopogon winterianus and Juniperus phoenicea EOs on planktonic and adherent B. cereus spores to stainless steel surfaces. Eleven strains of B. cereus were used in this study. The chemical composition of the C. winterianus and J. phoenicea oils was analyzed by gas chromatography (GC)/mass spectrometry (MS). Ninety components were identified for C. winterianus, being geranial (37 %), neral (29 %), beta-myrcene (16 %) and geraniol (4 %) the most abundant constituents. Twelve components were identified for J. phoenicea, being alpha-pinene (65 %) the most abundant constituent. The results of the minimal inhibitory concentration and minimal bactericidal concentration revealed that C. winterianus was the most effective EO (p < 0.05) against all eleven strains. In addition, there was a large log10 reduction (from 4.93 to 2.42; p < 0.05) between spores in planktonic form versus spores adhered to stainless steel surface. C. winterianus can be used for effective detachment of B. cereus spores capable to adhere and form biofilms on stainless steel surfaces, being a valid alternative for the development of natural disinfectant that may reduce negative effects of synthetic chemical disinfectants.

Accelerated Detection of Foodborne Pathogens and Toxins: Techniques and Applications – A Review

Pathogens associated with food and their corresponding toxins, including mycotoxins, pose a sig¬nificant threat to public health, leading to various health issues worldwide, particularly affecting infants, young children, and the elderly. The rise in foodborne illnesses highlights the crucial importance of food safety in ensuring a reliable food supply and promoting health. Timely detection of foodborne pathogens, toxins, and mycotoxins is essential for reducing the incidence of foodborne diseases. This review aims to provide comprehensive insights into the methodology for rapid detection, detailing the principles, appli¬cations, advantages, and limitations to enhance current knowledge. Conventional culture-based methods for foodborne pathogen identification are selective and are hindered by significant time demands, labor intensity, challenges from complex sample preparation, delayed results, and the need for specialized per¬sonnel. In contrast, the new emerging detection techniques such as immunological, nucleic acid-based, and biosensor-based methods offer time efficiency, reduced labor, improved accuracy, sensitivity, specificity, and reliability, and are user-friendly. Recently, numerous novel techniques have been developed for the rapid identification of foodborne pathogens, toxins, and mycotoxins, transforming food safety practices. Providing rapid and accurate results is crucial for controlling and managing foodborne disease outbreaks while ensuring food safety. As the global food supply chain becomes more complex, advancing rapid and automated detection methods remains essential for safeguarding food safety and quality, as well as enhanc¬ing public health.

An outbreak of acute diarrhoeal disease caused by Shigella sonnei in a village in Dibrugarh district, Assam.

Background & objectives Food and waterborne illnesses remain a neglected public health issue in India. Events with large gatherings frequently witness outbreaks of acute diarrheal diseases due to consumption of contaminated food or water or poor food handling practices. In the present study, an outbreak of acute diarrhoeal disease (ADD) occurring among the attendees of a birthday party in rural Dibrugarh district in the northeastern Indian State of Assam was investigated. Methods Sociodemographic information along with details of ADD outbreak that included information about source of foods, food handlers, illness details, etc., were collected using an outbreak investigation form for descriptive and analytical epidemiology. Rectal swabs from affected individuals and food handlers were collected along with bore-well water samples and tested in the laboratory by performing bacterial culture, biochemical analysis and polymerase chain reaction. Due to the delayed report on the outbreak, collecting leftover food for laboratory testing and analysis was impossible. Results A total of 25 cases of ADD had similar signs and symptoms. The mean incubation period for developing acute diarrhoea was 26.36±8.76 (± standard deviation) hours from food consumption. The overall attack rate was 60.04 per cent (25/41); 20 per cent (5/25) required hospitalization. Thirteen rectal swab samples were tested for pathogens and found positive for Shigella sonnei. Antibiotic susceptibility test of isolated S. sonnei showed resistance to nalidixic acid, ciprofloxacin and cefotaxime. Consumption of one of the food items - chicken curry was significantly associated with illness (Odds Ratio=14.8; 95% Confidence Interval: 2.75-85.11); P value<0.05 and Population Attributable Fraction (PAF) was 70.18 per cent. The water samples were found satisfactory for human consumption. Interpretation & conclusions The findings suggested that S. sonnei infection could be implicated in the investigated food-borne diarrhoeal disease outbreak and that there was a potential for human-poultry cross-infection. Additionally, the study revealed concerning levels of S. sonnei resistance to recommended antibiotics and drew attention to their public health relevance.

Insights into the fabrication and antibacterial effect of fibrinogen hydrolysate-carrageenan loading apigenin and quercetin composite hydrogels

Escherichia coli and Staphylococcus aureus are the most prevalent pathogenic bacteria, often resulting in the foodborne disease outbreaks through food spoilage and foodborne infections. To prevent and control food spoilage and foodborne infections induced by Escherichia coli and Staphylococcus aureus, the antibacterial hydrogels were fabricated using fibrinogen hydrolysate-carrageenan (AHs-C) and flavonoids (apigenin and quercetin), and the antibacterial effect of the composite hydrogels against Escherichia coli and Staphylococcus aureus was further investigated. The results of mechanical property exhibited that the composite hydrogels with 0.2 % of apigenin and quercetin (AHs-C-Ap/Que) showed the highest hardness and swelling property compared with the separate addition of apigenin or quercetin. Scanning electron microscopy and atomic force microscopy showed that the dense networks were formed in the hydrogels of AHs-C-Ap/Que., and the average roughness of AHs-C-Ap/Que. significantly increased to 30.70 nm compared with AHs-C. 1H NMR and FTIR spectra demonstrated that apigenin and quercetin were bound to AHs-C by hydrogen bond, hydrophobic interaction and Schiff base, where the interactions between Ap/Que. and AHs-C was stronger compared with the separate addition of apigenin or quercetin. The hydrogels of AHs-C-Ap/Que. showed the highest antibacterial capacity and antibacterial adhesion against Escherichia coli and Staphylococcus aureus. The antibacterial adhesion assay showed that 99 % removal ratios for E. coli and S. aureus were observed in AHs-C-Ap/Que. hydrogels, which showed a great potential to prevent food spoilage and foodborne 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.

Inhibitory Effects of Lactobionic Acid on Biofilm Formation and Virulence of Staphylococcus aureus.

Staphylococcus aureus biofilm is a common bio-contaminant source that leads to food cross-contamination and foodborne disease outbreaks. Hence, there is a need for searching novel antibiofilm agents with potential anti-virulence properties to control S. aureus contamination and infections in food systems. In this study, the antibiofilm effects of lactobionic acid (LBA) against S. aureus and its influence on virulence were explored. The minimum inhibition concentration of LBA on S. aureus was 8 mg/mL. Viable count and crystal violet assays revealed that LBA inhibited and inactivated S. aureus biofilms. Microscopic observations further confirmed the antibiofilm activity of LBA on S. aureus that disrupted the biofilm architecture and inactivated the viable cells in biofilms. Moreover, LBA decreased the release of extracellular DNA (eDNA) and extracellular polysaccharide (EPS) in S. aureus biofilms. LBA suppressed biofilm formation by intervening metabolic activity and reduced virulence secretion by repressing the hemolytic activity of S. aureus. Furthermore, LBA altered the expressions of biofilm- and virulence-related genes in S. aureus, further confirming that LBA suppressed biofilm formation and reduced the virulence secretion of S. aureus. The results suggest that LBA might be useful in preventing and controlling biofilm formation and the virulence of S. aureus to ensure food safety.

Forecasting hierarchical time series for foodborne disease outbreaks

Forecasting hierarchical time series for foodborne disease outbreaks

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.

Fix workforce problems in environmental health or risk further outbreaks of foodborne disease

Fix workforce problems in environmental health or risk further outbreaks of foodborne disease

Surveillance of household foodborne disease outbreaks in Zhejiang Province, China, 2010–2022

BackgroundFoodborne diseases are a growing public health concern worldwide and households are a common setting. This study aimed to explore the epidemiological characteristics of household foodborne disease outbreaks in Zhejiang Province and propose targeted prevention and control measures. MethodsDescriptive statistical methods were used to analyze household foodborne disease outbreak data collected from the Foodborne Disease Outbreaks Surveillance System in Zhejiang Province from 2010 to 2022. ResultsHousehold foodborne disease outbreaks showed an upward trend during the study period (Cox-Staurt trend test, p = 0.01563 < 0.05). These outbreaks mainly occurred from June to September, with 62.08% (352/567) of all reported outbreaks. The number of reported outbreaks varied in 11 prefectures, with a maximum of 100 and a minimum of only 7. Household foodborne disease outbreaks had a wide spectrum of etiologic factors. Mushroom toxins accounted for the largest proportion of all etiologies (43.39 %) and caused the highest proportion of hospitalization (54.18%) and death (78.26%). Such outbreaks are caused by accidently eating wild poisonous mushrooms. Bacterial infection (16.23%) was the second most common etiology, with Salmonella spp. and Vibrio parahaemolyticus being the primary pathogens. These outbreaks were caused by improper storage, improper processing or a combination of factors, and the foods involved were mainly aquatic animals, eggs and cooked meat. Other identified etiologies included plant toxins (9.52%), chemicals (7.23%), animal toxins (3.70%), and viruses (1.76%). Among the above-mentioned etiologies, mushroom toxins, bacteria, and animal toxins had seasonal characteristics. Analysis of regions and etiologies revealed that the proportion of various etiologies was different in 11 prefectures. Wild mushrooms (43.39%), aquatic animals (9.88%), and toxic plants (8.47%) were the top three foods involved in these outbreaks. The most common factors contributing to household foodborne disease outbreaks were inedibility and misuse (59.08%), followed by multiple factors (7.58%), improper storage (7.41%), and improper processing (7.41%). ConclusionsHousehold foodborne disease outbreaks were closely related to the lack of knowledge regarding foodborne disease prevention. Therefore, public health agencies should strengthen residents’ surveillance and health education to improve food safety awareness and effectively reduce foodborne diseases in households. In addition, timely publicity and early warning by relevant government departments, the introduction of standards to control the contamination of pathogenic bacteria in raw materials, and strengthened supervision of the sale of substances that may cause health hazards, such as poisonous mushrooms and nitrites, will also help reduce such outbreaks.

Listeria monocytogenes in Food Production and Food Safety: A Review

In the current world of global food distribution and marketing, the outbreak of a particular foodborne disease in a region may eventually occur in another part of the world at the same time. Foodborne diseases are estimated to cause over 600 million illnesses and 420,000 deaths each year. Listeriosis, a zoonotic bacterial disease caused by Listeria spp. has been reported in various parts of the world’s disease outbreak and incidence. The highest number of diseases and outbreaks is caused by Listeria monocytogenes and is highly predominant among elderly persons, immunocompromised individuals, pregnant women, and infants. This bacterium possesses the ability to survive and multiply under refrigeration temperature, a wide range of pH (4.1 - 9.6), and high salt (≤ 10%). The disease can be minimal (non-invasive/febrile gastroenteritis) and the pathogen possesses the ability to cross the epithelium and infect sterile organs (invasive). Outside food contamination, resistance to antibiotics by Listeria monocytogenes poses major public health concerns as this bacterium has developed resistance to various antibiotics in use. In addition to food, Listeria species have been isolated from the soil, water, plants, fruits, and vegetables coupled with the long incubation period (11 - 70 days), which poses a challenge to infection source identification and trace back principle. Controlling Listeria in foods can be achieved by practicing a Hazard Analysis and Critical Control Point (HACCP) strategy in the food industry, improving hygiene measures, and avoiding the consumption of contaminated foods. Also, susceptible individuals should be educated on the risks associated with the consumption of contaminated foods.

Imprinted membrane-covalent organic framework platform for efficient label-free visual detection of Listeria monocytogenes and Salmonella typhimurium in food samples

BackgroundRapid and sensitive detection of foodborne pathogens in food plays a crucial role in controlling outbreaks of foodborne diseases, of which Listeria monocytogenes and Salmonella typhimurium are representative and notable pathogens. Thus, it's of great importance to achieve the effective detection of these pathogens. However, the most common detection methods (culture-based technique, Polymerase Chain Reaction and immunological methods) have disadvantages that cannot be ignored, such as time-consuming, laborious, complex sample preparation process, and the possibility of cross-reaction. Hence, it is essential to develop a facile detection method for the pathogens with high sensitivity and specificity to avoid the above-mentioned disadvantages. ResultsWe report a label-free visual platform for the simultaneous capture and detection of Listeria monocytogenes and Salmonella typhimurium. For the first time, we have prepared polydimethylsiloxane-Chromotrope 2R membrane which serves as the substrate for bacterial capture and enrichment through the formation of specific recognition sites. The positively charged Pt-covalent organic framework combines with the pathogens through surface charge interaction, thereby the label-free sandwich platform is formed. Remarkable peroxidase activity of Pt-covalent organic framework converts the conversion of bacterial quantity into amplified color signal by catalyzing 3,3′,5,5′-Tetramethylbenzidine to oxidized 3,3′,5,5′-Tetramethylbenzidine. The platform demonstrates the capability to identify two representative food-borne pathogens within a time frame of 100 min, exhibiting high sensitivity and excellent specificity without the interference from non-target bacteria. The limit of detection of the visual platform toward Listeria monocytogenes and Salmonella typhimurium was 1.61 CFU mL−1 and 1.31 CFU mL−1, respectively. And the limit of quantification toward Listeria monocytogenes and Salmonella typhimurium was 4.94 CFU mL−1 and 2.47 CFU mL−1, respectively. The relative standard derivations of the visual platform for both bacteria were lower than 4.9 %. Furthermore, our proposed platform has obtained reliable and satisfactory results on analyzing diverse food samples. SignificanceThis research expands the application of a label-free platform combined with unlabeled nanocomponents in the rapid isolation and detection of diverse of food-borne pathogens. The platform possesses the advantages of simple operation and real-time monitoring, without complicated sample pretreatment process. The whole detection process can realize the simultaneous monitoring of Listeria monocytogenes and Salmonella typhimurium within 100 min. Furthermore, it is also of reference significance for the detection of other common pathogens.

Mushroom poisoning of Panaeolus subbalteatus from Ningxia, northwest China, with species identification and tryptamine detection

Mushroom poisoning is a significant contributor to foodborne disease outbreaks in China. This study focuses on two Panaeolus subbalteatus poisoning incidents accompanied by epidemiological investigations, species identification, and toxin detection in Ningxia, northwest China. In these two poisoning incidents, some patients exhibited gastrointestinal or neurological symptoms approximately 0.5 h after ingestion of a large amount of wild mushroom. Specifically, in Case 1, one of the three patients experienced nausea, vomiting, and numbness in the throat and limbs; in Case 2, one patient reported dizziness and an abnormal sense of direction. Through morphological and phylogenetic analyses, mushroom specimens were identified as P. subbalteatus. Psilocybin and psilocin were detected in mushroom samples, and only psilocin was detected in biological samples by liquid chromatography-triple quadrupole-linear ion trap mass spectrometry screening. The average psilocybin and psilocin contents in mushroom samples were 1532.2–1760.7 and 114.5–136.0 mg/kg (n = 3), respectively. Moreover, only psilocin was detected in blood and urine samples, with average concentrations 0.5–1.2 ng/mL (n = 3) and 2.5–3.1 ng/mL (n = 3), respectively. These findings provide technical support for managing similar incidents in the future.