Foodborne Infections Research Articles

Prevalence of cpe-positive Clostridium perfringens in surface-attached soil of commercially available potatoes and its significance as a potential source of food poisoning

ObjectiveWe aimed to examine the surface-attached soil of commercially available potatoes in Japan to determine the association between foodborne infection and the circulation of Clostridium perfringens through vegetables, soil, and environments. MethodsC. perfringens spores were isolated from 30 surface-attached soil samples of potatoes obtained from six regions in Japan. We performed multiplex polymerase chain reaction (PCR) and sequencing to detect the presence of six toxin and plasmid-related genes in the isolates. ResultsSulfite-reducing clostridial spores were detected in 28 (93%) of 30 potato samples, and toxin gene PCR was performed using 613 isolates. The C. perfringens α toxin gene (cpa) was detected in 288 isolates (288/613; 47%) from 25 potato samples (83%), and these isolates were presumed to be the strains of C. perfringens. The toxin types of C. perfringens were classified into type A, in which 73% of isolates had only cpa, followed by type F in 20%, type C in 6%, and type E in 0.003% (1 isolate). The enterotoxin gene (cpe) related to food poisoning was detected in 64 isolates from 9 potato samples (3%). Of these, 59 isolates had cpa and cpe, whereas five had cpa, C. perfringens β toxin gene, and cpe. All tested cpe-positive isolates had plasmid-type cpe. ConclusionsThe isolation of culturable cpe-positive C. perfringens from the surface-attached soil of commercially available potatoes indicates that potatoes are a potential source of foodborne transmission of C. perfringens.

Food safety risk perceptions and mitigation techniques in the dumpster diving community in Sweden

An online questionnaire was used to investigate behaviors and habits relating to food retrieval by Swedish dumpster divers. Respondents were also asked to share information on their background, reasons for engaging in dumpster diving, and perceptions of potential bacterial hazards associated with the consumption of discarded foods. The questionnaire was mainly distributed to Swedish social media groups focusing on dumpster diving, and a total of 92 responses were received. The most common reason given for engaging in dumpster diving was to reduce food waste and associated negative environmental impacts (60%, n = 55). Many of the respondents (65%) had completed university education, and around three-quarters (73%) had some form of employment or were enrolled in studies. Half the respondents (52%, n = 48) perceived a risk of falling ill after consuming food obtained through dumpster diving, but very few (2%) reported they had been made ill by food they had picked up from dumpsters. Around one-fifth (22%) of the respondents did not know of any bacteria that could cause foodborne infections or food poisoning. Salmonella was mentioned by 35% of the respondents, while Listeria was mentioned by 18%. The respondents reported employing various techniques to reduce the risk of encountering harmful microbiological agents, for example, rinsing their food retrievals or discarding food that appeared spoiled. These are novel findings on dumpster divers’ perceptions of perceived health risks and the strategies they use to mitigate such risks with food obtained through dumpster diving.

Mutations in atpG2 may confer resistance to gentamicin in Listeria monocytogenes.

Introduction Listeriosis, a foodborne infection caused by Listeria monocytogenes, could lead to febrile listerial gastroenteritis and a more invasive form which is often associated with a high mortality and hospitalisation rate. Gentamicin, used as an adjunct therapy with ampicillin, remains the treatment of choice for this life-threatening and invasive infection.Gap statement Nevertheless, there is little data on gentamicin resistance determinants in L. monocytogenes.Aim In this study, we selected and characterised B2b, a gentamicin-resistant mutant derived from L. monocytogenes ATCC 19115 to determine the target(s) of resistance in L. monocytogenes after exposure to gentamicin.Methodology Whole-genome sequencing was carried out to identify the mutation site(s) and possible mechanism(s) of resistance. The mutant was characterised using antimicrobial susceptibility testing and PCR. For biological verifications, complementation and allelic exchange mutagenesis were carried out.Results We found that the gentamicin resistance in B2b was caused by a 10 bp deletion in atpG2 which encodes a gamma subunit of the ATP synthase in L. monocytogenes. Using atpG2 PCR, various other mutations were identified in other gentamicin resistant mutants derived from ATCC 19115. In addition, the mutation from B2b, when introduced into L. ivanovii, also caused gentamicin resistance in this Listeria species.Conclusion Hence, atpG2 mutations appear to be important determinants of gentamicin resistance not only in L. monocytogenes but possibly also in other Listeria species.

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

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

Optical Methods for Label-Free Detection of Bacteria

Pathogenic bacteria are the leading causes of food-borne and water-borne infections, and one of the most serious public threats. Traditional bacterial detection techniques, including plate culture, polymerase chain reaction, and enzyme-linked immunosorbent assay are time-consuming, while hindering precise therapy initiation. Thus, rapid detection of bacteria is of vital clinical importance in reducing the misuse of antibiotics. Among the most recently developed methods, the label-free optical approach is one of the most promising methods that is able to address this challenge due to its rapidity, simplicity, and relatively low-cost. This paper reviews optical methods such as surface-enhanced Raman scattering spectroscopy, surface plasmon resonance, and dark-field microscopic imaging techniques for the rapid detection of pathogenic bacteria in a label-free manner. The advantages and disadvantages of these label-free technologies for bacterial detection are summarized in order to promote their application for rapid bacterial detection in source-limited environments and for drug resistance assessments.

In Vitro Assessment of Antimicrobial Activity of Phytobiotics Composition towards of Avian Pathogenic Escherichia coli (APEC) and Other E. coli Strains Isolated from Broiler Chickens.

Escherichia coli infections (including APEC) in broiler chickens are not only a health and economic problem of the flock, but also a significant health threat to poultry meat consumers. The prophylactic and therapeutic effects of the phytobiotic composition on E. coli in broiler chickens were previously described. However, most of the data were related to the reference strains (for both in vitro and in vivo models). Based on the previous studies in human and animals, E. coli strains seem to be multidrug resistance. This, in turn, makes it necessary to develop effective alternative methods of treating this type of infection already at the stage of poultry production. In the present study, the antibacterial activity against various strains of E. coli (including APEC) was assessed for two innovative phytobiotics mixtures: H1, containing thymol, menthol, linalool, trans-anethole, methyl salicylate, 1,8-cineol, and p-cymene; H2, in addition to compounds from H1, containing terpinen-4-ol and γ-terpinene. The unique mixtures of phytobiotics used in the experiment were effective against various strains of E. coli, also against APEC, isolated from broiler chickens from traditional industrial breeding, as well as against those showing colistin resistance. The minimum inhibitory concentration (MIC) values for these unique mixtures were: For H1 1:512 for APEC and non-APEC E. coli strains isolated from day old chicks (DOCs), 1:512 for non-APEC, and 1:1024 for non-APEC isolated from broilers sample. For mixture H2, MIC for APEC from both type of samples (DOCs and broilers) was 1:1024 and for non-APEC (DOCs and broilers) was 1:512. The results suggest that phytobiotic compositions used in this study can be successfully used as a natural alternative to antibiotics in the treatment of E. coli infections in broiler chickens. The promising results may be a crucial point for further analyses in broiler flocks exposed to E. coli infections and where it is necessary to reduce the level of antibiotics or completely eliminate them, thus reducing the risk of foodborne infections.

Human norovirus contamination challenge in fresh produce: a global prevalence and meta-analytic assessment.

Among fresh produce (FP)-associated foodborne infections, human noroviruses (HNoV) are the leading causative agent. The present study aimed to assess the prevalence of HNoV in FP. FP-associated HNoV records mined from 5 repositories until 25/05/2022 according to PRISMA standards were appraised, fitted to a generalized linear mixed-effects model and subgroup analysed by sample type, genogroup, and geographical location. Further, heterogeneity was assessed in the model coupled with a leave-one-out-cross-validation. The overall prevalence of HNoV in FP was 9.3% (95% confidence interval [CI] 3.7-21.7. HNoV prevalence was higher in fruits (9.8%[3.7-23.5]) than vegetables (9.4%[3.1-25.3]). Regarding geographical distribution, FP-associated HNoV prevalence varied from Africa (25.8%, 5.7-66.7), Asia (23.2%[4.6-65.0]), Europe (5.6%[0.7-33.9]), North America (12.4%[1.8-52.7]) to South America (7.5%[0.0-100.0]). HNoV GI overall prevalence in FP was 5.3% (2.5-11.1) and varied by sample type (fruits: 4.9%[1.7-13.2]; vegetables: 5.8%[1.6-18.8]). While the occurrence of GII in FP was 1.7% (0.7-3.9) and varied by sample type (fruits: 2.5%[1.0-6.5]; vegetables: 0.9%[0.2-4.9]), GIGII (detection of both GI and GII) was 0.3% (0.1-1.0) with 0.4% (0.1-2.2) and 0.2% (0.0-1.5) in fruits and vegetables, respectively. In all cases, the test for sample/regional prevalence differences were not significantly different with the exception of GII regional prevalence differences (p = 0.03). This study suggests that FP represents a critical vehicle for HNoV dissemination, a global and a high risk for public health.

Thermal inactivation kinetics of uropathogenic Escherichia coli in sous-vide processed chicken breast

Chicken is a suspected reservoir of uropathogenic Escherichia coli (UPEC), resulting in foodborne urinary tract infections (UTIs). Sous-vide ready-to-eat (RTE) food products may be associated with microbial hazards due to the low-temperature long-time (LTLT) process. However, little is known regarding the survival of UPEC during sous-vide cooking. The aim of this study was to evaluate the heat resistance of UPEC in chicken breast during sous-vide processing and establish predictive inactivation models. Chicken breast samples were inoculated with a four-strain cocktail of UPEC, including reference strains from UTI patients and chicken isolates. The inoculated samples, with or without 3% NaCl solution for marination, were vacuum sealed in bags, immersed in a temperature-controlled water bath, and cooked at 50 °C, 55 °C, 60 °C, and 63 °C. The change in survival of populations of UPEC was fitted with the linear and Weibull inactivation models to obtain the survival curves at different temperatures; the D- and z-values were also calculated. The goodness-of-fit was evaluated using the root mean square error (RMSE), sum of squared errors (SSE), adjusted R2, and Akaike information criterion (AIC). The results showed that the linear model with tail was better than the Weibull model in terms of fitting performance. With the addition of salt marinade, D-values at 50 °C, 55 °C, 60 °C, and 63 °C determined by the linear model with tail decreased from 299.78 to 166.93 min, 16,60 to 13.87 min, 4.06 to 3.05 min, and 1.05 to 0.87 min, respectively, compared with the controls. The z-values of control and salt-marinated samples were 6.14 °C and 5.89 °C, respectively. The model developed for predicting UPEC survival under sous-vide cooking was validated using an additional survival curve at 58 °C. The validation results showed that the RMSE was 0.122 and 0.133 log CFU/g, and the proportion of relative error was 0.875 and 0.750 in the acceptable prediction zones for the control and salt-marinated samples, respectively. In conclusion, the heat resistance of an emerging foodborne pathogen, UPEC, in sous-vide processed chicken breast was revealed for the first time. Our results showed that salt marinade (3% NaCl) increases the heat sensitivity of UPEC during the sous-vide processing. The developed survival functions based on the linear model with tail can be applied to control the thermal lethality of UPEC.

Food Safety Attitudes, Behaviors, and Hygiene Measures among Predominantly Low-Income Parents in Houston, Texas

Foodborne infections in the United States affect racial-ethnic minority and low-income populations at higher rates than the general population. To identify the prevalence of food safety behaviors and demographic characteristics associated with food handling practices among a susceptible, high-risk population, a cross-sectional survey was administered to 106 parents with children enrolled at two elementary schools serving predominantly low-income families in Houston, Texas. Relationships between demographic characteristics and food safety behavioral outcomes were examined using cross-tabulations and Fisher's exact test. Most respondents were female (93.4%), Hispanic, Latino, or Mexican American (94.9%), and had no previous food handling employment experience (75.0%). The primary source of food safety information reported was the Internet (32.7%), and nearly half of parents (42.7%) reported that they did not consider contamination of food with germs a serious food safety problem. Hand washing before food preparation was more common (98.0%) than before touching the refrigerator handle (66.3%), after electronic device use (55.6%), or after handling raw animal proteins (77.6%). The prevalence of fresh fruit (98.0%) and vegetable (97.9%) washing and appropriate contaminated cutting board handling (89.0%) was high among parents. Self-reported gaps in food handling behaviors identified included lack of food thermometer ownership (80.4%), use of reusable cleaning tools (71.0%), inappropriate defrosting methods (67.4%), and washing of raw poultry (86.3%), seafood (84.9%), and meat (74.7%). Hand washing after electronic device use and defrosting methods were observed to vary significantly according to demographic characteristics. Food safety education with messages targeted to specific demographic groups may be necessary to reduce the risk of foodborne disease among low-income parents and young children.

A Systematic Review of Food Hygiene Control in Food Service Providers: Review from 2000 - 2022

From production through the intake, food hygiene particularly applies to the situations and processes that must be followed from production to consumption to guarantee the safety of the food produced. Food contamination may occur throughout the butchering or collecting, manufacturing, storage, distribution, transportation, and preparation processes. Food hygiene is described as “all circumstances and measures required throughout production, processing, storage, distribution, and preparation to guarantee the food is clean, healthy, and edible” Foodborne infections and even death can result from proper food hygiene. Around the world, contaminated food causes 600 million cases of foodborne disease and 420,000 deaths each year. Nearly 30% of all foodborne deaths worldwide occur in children under five. Campylobacter and norovirus are the main culprits found in most foodborne cases reported. Therefore, this research aims to assess food service providers' food hygiene knowledge, attitude, and practice at various phases of food supply. Moreover, this research also focused on different parts of the food supply chain, such as processing, manufacturing, and cooking. This review will also help develop stricter regulations and guidelines for food service providers to prevent more foodborne diseases. Keywords: food hygiene; foodborne diseases; food service providers; food handlers.

Antibiotics Resistant Pattern of Bacteria Isolated from Spoiled Avocado Fruit Sold in Sokoto Metropolis

Consuming fruit contaminated with bacteria remains a crucial route of foodborne infection in developing countries and creates a severe public health burden. The research aimed to determine the antibiotic-resistant pattern of bacteria associated with the spoilage of Avocado pear (Persea americana) sold in the Sokoto metropolis. Twenty spoilt avocado fruits were obtained from market three in Sokoto Metropolis. The bacteriological analysis was carried out using the pour plate method. The antibiotic resistance pattern was determined using the Kirby-Bauer disk diffusion method. A total of five species of bacteria were isolated and identified in this study. The mean and standard error of total viable bacterial counts of avocado samples across three different locations ranged from 4.20±5.77 to 8.43±33.49 (x 104CFU/g). A total of 19 bacterial isolates were identified from avocado samples. Staphylococcus aureus had the highest frequency of occurrence, 16 (29.2%), while Klebsiella sp. had the lowest frequency of occurrence, 7 (12.7%). Among all antibiotics tested against bacterial species, Escherichia coli isolates were found to have 10 (91%) and 9 (82%) resistance against ciprofloxacin and streptomycin, respectively. Pseudomonas sp. was found to be 100% resistant to chloramphenicol and Septrin (cotrimoxazole). However, S. aureus was found to have 12 (72%) resistance to pefloxacin. Similarly, Klebsiella spp. were found to be 7 (100%) resistant to Septrin. Isolation of these bacterial species, especially E. coli from avocado samples analyzed, is of public health significance, especially the presence of antibiotic resistance species.

Zatrucia i zakażenia pokarmowe w Polsce w latach 2018-2020

The purpose of this study is to assess the epidemiological situation of foodborne infections and intoxications in Poland in the years 2018-2020. The evaluation was based on the analysis of information sent to Department of Epidemiology NIPH NIH - NRI through ROE (pol. Rejestr Ognisk Epidemicznych) - an electronic system created for uploading, transfer and analysis of data acquired during the outbreak investigations. Additional sources for the analysis were NIPH NIH - NRI annual bulletins (Czarkowski MP et al. "Infectious diseases and poisonings in Poland", 2014-2020. Warsaw, NIPH NIH and GIS). In the years 2018-2020 a total number of 2,108 foodborne outbreaks were reported in which 52,175 persons were exposed and 17,023 got sick (in 2016 n=916, in 2019 n=918, in 2020 n=274). In 2020 over 3 fold decrease in the number of outbreaks comparing to 2019 and over 4 fold decrease in the number of cases in those outbreaks was observed. Among outbreaks which took place in 3 most frequent settings (private household, food facility and hospital) the steepest decrease was in 12th week of 2020 (ISO 2020-W12). The most frequent etiological agent of outbreaks in the years 2018-2020 was Salmonella sp. (38.3% of outbreaks in 2018, 32.7% in 2019 and 47.8% in 2020) and specifically serotype Enteritidis (38.3%, 27% and 39.4% accordingly). The most frequent setting of outbreaks was private household (59.7% outbreaks in 2018, 66% in 2019 and 62% in 2020), followed by hospital (17.4%, 18.3% i 19.7% accordingly). Up until 2019 an increasing trend in the number of small outbreaks (up to 4 cases) caused by Salmonella sp. was observed (in 2018 - 605 and in 2019 - 612 were reported). Decrease in the number of outbreaks in selected settings from 12th ISO week of 2020 might have been due to introduction of restrictions during COVID-19 pandemic and enhancement of personal hygiene practices. An increase in identified and registered small outbreaks caused by Salmonella sp. comparing to the median of the number of those outbreaks from 2014-2016 could partly be a result of routine surveillance enhancement after introducing System for Registry of Epidemiological Interviews (pol. SRWE).

Molecular typing and genome sequencing allow the identification of persistent Listeria monocytogenes strains and the tracking of the contamination source in food environments

The presence of Listeria monocytogenes (Lm) in the food processing environment (facilities and products) is a challenging problem in food safety management. Lm is one of the main causes of mortality in foodborne infections, and the trend is continuously increasing. In this study, a collection of 323 Lm strain isolates recovered from food matrices and food industry environments (surfaces and equipment) over four years from 80 food processing facilities was screened using a restriction site-associated tag sequencing (2b-RAD) typing approach developed for Lm. Thirty-six different restriction site-associated DNA (RAD) types (RTs) were identified, most of which correspond to lineage II. RT1, the most represented genotype in our collection and already reported as one of the most prevalent genotypes in the food environment, was significantly associated with meat processing facilities. The sequencing of the genomes of strains belonging to the same RT and isolated in the same facility in different years revealed several clusters of persistence. The definition of the persistent strains (PSs) allowed the identification of the potential source of contamination in the incoming raw meat that is introduced in the facility to be processed. The slaughterhouses, which, according to the European Union (EU) regulation, are not inspected for the presence of Lm could be hotspots for the persistence of Lm PSs.

Purification and characterization of bacteriocin produced by a strain of Lacticaseibacillus rhamnosus ZFM216.

The recent surge in demand for natural preservatives has ushered in a new era of research into novel bacteriocins capable of effectively combating food-borne infections. In this study, the bacteriocin from Lacticaseibacillus rhamnosus ZFM216, which has a molecular mass of 11851.9 Da, was purified using macroporous resin, gel chromatography, and reversed-phase high performance liquid chromatography. This bacteriocin could inhibit both Gram-positive and Gram-negative bacteria. It had a strong inhibitory effect on Staphylococcus aureus D48 with minimum inhibitory concentration values of 1.75 μM. Bacteriocin ZFM216 was heat stable and showed pH stability under weakly acidic conditions. It was sensitive to pepsin, proteinase K and trypsin. Electron microscopy results showed that when treated with bacteriocin ZFM216, S. aureus D48 was severely deformed, the cell structure was obviously changed, and the intracellular electrolyte leaked to the outside of the cell. Bacteriocin ZFM216 caused the ATP level of the indicator to decrease, the conductivity to sharply increase, and the transmembrane potential difference (ΔΨ) to instantaneously decrease. This research formed the basis for further development and utilization of bacteriocin ZFM216 which has potential in the food industry.

Estimating the burden of foodborne gastroenteritis due to nontyphoidal Salmonella enterica, Shigella and Vibrio parahaemolyticus in China.

To estimate the incidence of foodborne gastroenteritis caused by nontyphoidal Salmonella enterica, Shigella, and Vibrio parahaemolyticus in China, population surveys and sentinel hospital surveillance were implemented in six provinces from July 2010 to July 2011, and a multiplier calculation model for the burden of disease was constructed. The multiplier for salmonellosis and V. parahaemolyticus gastroenteritis was estimated at 4,137 [95% confidence interval (CI) 2,320-5,663], and for shigellosis at 4,356 (95% CI 2,443-5,963). Annual incidence per 100,000 population was estimated as 245 (95% CI 138-336), 67 (95% CI 38-92), and 806 (95% CI 452-1,103) for foodborne salmonellosis, shigellosis, and V. parahaemolyticus gastroenteritis, respectively, indicating that foodborne infection caused by these three pathogens constitutes an important burden to the Chinese healthcare system. Continuous implementation of active surveillance of foodborne diseases, combined with multiplier models to estimate disease burden, makes it possible for us to better understand food safety status in China.

Antibiofilm properties of bioactive compounds from Actinomycetes against foodborne and fish pathogens

In nature, bacteria can form biofilms, multi-layered structures that adhere microbial populations to solid surfaces by exopolysaccharides, proteins, and nucleic acids. In addition to causing foodborne infections, biofilms can be a major problem in aquaculture. Actinomycetes extracts have previously demonstrated antibiofilm activity against multiple foodborne and fish pathogens, and further characterization of these extracts is needed. In this study, we identified the chemical structures and antibiofilm properties of four extracts and determined the genetic similarity of the isolates to known Streptomyces isolates. We found that several extracts contained multiple antibiofilm compounds, and the antibiofilm activities of all extracts were most stable at pH 6. Furthermore, the antibiofilm inhibition and destruction activities of the isolates were stable at different temperatures. All of crude extracts demonstrated activity against biofilms formed by foodborne and fish pathogens on the surface of stainless-steel coupons as well as polystyrene that commonly used in industrial equipment. Using PCR 16S-rRNA gene and DNA sequencing analysis, the four Actinomycetes isolates were found to be 99% (1 AC), 97% (20 PM), 95% (16 PM), and 85% (18 PM) similar to Streptomyces. Biofilm structure were analyzed using Scanning Electron Microscopy coupled with Energy-Dispersive Spectrometry analysis. Coniine/(S)-2-propylpiperidine was the most active fraction of the crude extracts of the 1 AC, 20 PM, and 16 PM isolates, and piperidine, 2-(tetrahydro-2-furanyl) was most active in the 18 PM isolate.

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

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

Luminal and mucosa-associated caecal microbiota of chickens after experimental Campylobacter jejuni infection in the absence of Campylobacter-specific phages of group II and III.

Campylobacteriosis is still the most commonly reported zoonosis in the European Union causing gastrointestinal disease in humans. One of the most common sources for these food-borne infections is broiler meat. Interactions between Campylobacter (C.) jejuni and the intestinal microbiota might influence Campylobacter colonization in chickens. The aim of the present study was to gain further knowledge about exclusive interactions of the host microbiota with C. jejuni in Campylobacter-specific phage-free chickens under standardized conditions and special biosafety precautions.Therefore, 12 artificially infected (C. jejuni inoculum with a challenge dose of 7.64 log10 c.f.u.) and 12 control chickens of the breed Ross 308 were kept under special biosafety measures in an animal facility. At day 42 of life, microbiota studies were performed on samples of caecal digesta and mucus. No Campylobacter-specific phages were detected by real-time PCR analysis of caecal digesta of control or artificially infected chickens. Amplification of the 16S rRNA gene was performed within the hypervariable region V4 and subsequently sequenced with Illumina MiSeq platform. R (version 4.0.2) was used to compare the microbiota between C. jejuni-negative and C. jejuni-positive chickens. The factor chickens' infection status contributed significantly to the differences in microbial composition of mucosal samples, explaining 10.6 % of the microbiota variation (P=0.007) and in digesta samples, explaining 9.69 % of the microbiota variation (P=0.015). The strongest difference between C. jejuni-non-infected and C. jejuni-infected birds was observed for the family Peptococcaceae whose presence in C. jejuni-infected birds could not be demonstrated. Further, several genera of the family Ruminococcaceae appeared to be depressed in its abundance due to Campylobacter infection. A negative correlation was found between Christensenellaceae R-7 group and Campylobacter in C. jejuni-colonised chickens, both genera potentially competing for substrate. This makes Christensenellaceae R-7 group highly interesting for further studies that aim to find control options for Campylobacter infections and assess the relevance of this finding for chicken health and Campylobacter colonization.

In Vitro Evaluation of the Broad-Spectrum Antimicrobial Potential of Lactic Acid Bacteria Isolated from Milk Whey and Nunu for Veterinary Applications

Background Information One of the characteristic of bacteria zoonoses diseases is their tendency to re-emerge, as such they said to be responsible for a very high proportion of morbidity and mortality. Many documented zoonotic diseases and reported to be resistant to some conventional antibiotics. Similarly challenging is the fact that most of the antibiotics currently being used against these diseases are reported not to be completely metabolized and are often released in unmetabolized forms which when they find their ways into the food chain becomes health issue. Metabolites from some Lactic Acid Bacteria are being harnessed as a bio-active compounds for the novel unconventional control of these diseases which this research seeks to make contribution. Abstract Zoonoses incidences continue to play significant roles in both human and veterinary medicine and their eradication especially in the developing country like Nigeria, is difficult. Zoonotic food-borne infections caused by Gram-positive and Gram-negative bacteria are re-emerging. Several findings indicated that the cell-free supernatant derived from some Lactic Acid Bacteria have some antibacterial effects when applied directly or added to food during packaging. The aim of this study was to investigate the in vitro antagonistic effect of cell-free supernatant derived from some LAB species isolated from whey and Nunu (obtained from a locally fermented milk product) against some zoonotic bacteria pathogens (Escherichia coli, Salmonella sp. and Staphylococcus aureus. Streptococcus sp. and Salmonella sp. Four (4) LAB isolates were isolated, identified using basic morphological and biochemical characterization and screened on the basis of functional and technological characterization. The Cell-free supernatant from these strains, Lactobacillus casei LB01, Lactobacillus sp. LB02, Lactobacillus acidophilus LB03 and Lactobacillus plantarum LB04 were prepared by centrifugation at 10,000 rpm for 5 minutes and used against the indicator organisms at 107 CFU/ml using agar well diffusion method. The cell-free supernatant inhibited the growth of both Gram- positive and Gram-negative bacteria strains of veterinary origins. Our findings suggest that the LAB strains have the potential for antibiotic alternatives for the control of several zoonotic diseases. This holds a great advantage in the current efforts to tackling and reducing the prevalence and spread of zoonotic diseases which are re-emerging in Nigeria

Prevalence and characterisation of Bacillus cereus in cooked rice retailed in Ilara-mokin, Nigeria

Bacillus cereus is widely distributed in different food products and causes a variety of symptoms associated with food poisoning. Rice has been suggested as a vehicle for contamination and being involved in B. cereus intoxication. Based on the aforementioned risks, studies of Bacillus cereus incidence along with its isolation and characterization are essential to establishing the safety of cooked rice. Using the selective culture technique, pure isolates of Bacillus cereus strains were characterized and identified based on cultural, and biochemical features. Characterization was done on the ability of the bacterial strains to hydrolyse casein and starch, ferment lactose, and lyse red blood cells (haemolysis). Out of the 47 samples screened, 45 isolates were detected in 14 samples. Antibiotic susceptibility testing revealed that all isolates showed resistance to Ampicillin (10 μg), but were susceptible to Erythromycin (15 μg), Vancomycin (30 μg), Tetracycline (30 μg), Ampicillin (10 μg), Gentamicin (10 μg), and Chloramphenicol (30 μg). 62.2%, 64.4%, 0% and 46.7% were capable of producing amylase, protease, ferment lactose and lyse red blood cells respectively. This study shows that 14 samples out of 47 samples of cooked rice in this work has the possible risk of foodborne infections/ intoxication that occurs as a result of the possibility of the development of B. cereus in favourable conditions and consumption of these products. Basically, prevention is by proper handling of raw materials, controlling the temperature of cooking and storing rice, and personal hygiene of food handlers.