A possible route for foodborne transmission of Clostridium difficile?

One Health Perspectives on Food Safety in Minimally Processed Vegetables and Fruits: From Farm to Fork

While food markets and food production chains are experiencing exponential growth, global attention to food safety is steadily increasing. This is particularly crucial for ready-to-eat products such as fresh-cut salads and fruits, as these items are consumed raw without prior heat treatment, making the presence of pathogenic microorganisms quite frequent. Moreover, many studies on foodborne illnesses associated with these foods often overlook the transmission links from the initial contamination source. The prevention and control of the dissemination of foodborne pathogens should be approached holistically, involving agricultural production, processing, transport, food production, and extending to final consumption, all while adopting a One Health perspective. In this context, our objective is to compile available information on the challenges related to microbiological contamination in minimally handled fruits and vegetables. This includes major reported outbreaks, specific bacterial strains, and associated statistics throughout the production chain. We address the sources of contamination at each stage, along with issues related to food manipulation and disinfection. Additionally, we provide potential solutions to promote a healthier approach to fresh-cut fruits and vegetables. This information will be valuable for both researchers and food producers, particularly those focused on ensuring food safety and quality.

Update on Commonly Used Molecular Typing Methods for Clostridioides difficile

This review aims to provide a comprehensive overview of the significant Clostridioides difficile molecular typing techniques currently employed in research and medical communities. The main objectives of this review are to describe the key molecular typing methods utilized in C. difficile studies and to highlight the epidemiological characteristics of the most prevalent strains on a global scale. Geographically distinct regions exhibit distinct strain types of C. difficile, with notable concordance observed among various typing methodologies. The advantages that next-generation sequencing (NGS) offers has changed epidemiology research, enabling high-resolution genomic analyses of this pathogen. NGS platforms offer an unprecedented opportunity to explore the genetic intricacies and evolutionary trajectories of C. difficile strains. It is relevant to acknowledge that novel routes of transmission are continually being unveiled and warrant further investigation, particularly in the context of zoonotic implications and environmental contamination.

Antibiotic Resistance in Selected Emerging Bacterial Foodborne Pathogens-An Issue of Concern?

Antibiotic resistance (AR) and multidrug resistance (MDR) have been confirmed for all major foodborne pathogens: Campylobacter spp., Salmonella spp., Escherichia coli and Listeria monocytogenes. Of great concern to scientists and physicians are also reports of antibiotic-resistant emerging food pathogens-microorganisms that have not previously been linked to food contamination or were considered epidemiologically insignificant. Since the properties of foodborne pathogens are not always sufficiently recognized, the consequences of the infections are often not easily predictable, and the control of their activity is difficult. The bacteria most commonly identified as emerging foodborne pathogens include Aliarcobacter spp., Aeromonas spp., Cronobacter spp., Vibrio spp., Clostridioides difficile, Escherichia coli, Mycobacterium paratuberculosis, Salmonella enterica, Streptocccus suis, Campylobacter jejuni, Helicobacter pylori, Listeria monocytogenes and Yersinia enterocolitica. The results of our analysis confirm antibiotic resistance and multidrug resistance among the mentioned species. Among the antibiotics whose effectiveness is steadily declining due to expanding resistance among bacteria isolated from food are β-lactams, sulfonamides, tetracyclines and fluoroquinolones. Continuous and thorough monitoring of strains isolated from food is necessary to characterize the existing mechanisms of resistance. In our opinion, this review shows the scale of the problem of microbes related to health, which should not be underestimated.

The Environment, Farm Animals and Foods as Sources of Clostridioides difficile Infection in Humans

The recent discovery of the same Clostridioides difficile ribotypes associated with human infection in a broad range of environments, animals and foods, coupled with an ever-increasing rate of community-acquired infections, suggests this pathogen may be foodborne. The objective of this review was to examine the evidence supporting this hypothesis. A review of the literature found that forty-three different ribotypes, including six hypervirulent strains, have been detected in meat and vegetable food products, all of which carry the genes encoding pathogenesis. Of these, nine ribotypes (002, 003, 012, 014, 027, 029, 070, 078 and 126) have been isolated from patients with confirmed community-associated C. difficile infection (CDI). A meta-analysis of this data suggested there is a higher risk of exposure to all ribotypes when consuming shellfish or pork, with the latter being the main foodborne route for ribotypes 027 and 078, the hypervirulent strains that cause most human illnesses. Managing the risk of foodborne CDI is difficult as there are multiple routes of transmission from the farming and processing environment to humans. Moreover, the endospores are resistant to most physical and chemical treatments. The most effective current strategy is, therefore, to limit the use of broad-spectrum antibiotics while advising potentially vulnerable patients to avoid high-risk foods such as shellfish and pork.

Microbiological Safety and Quality of Meals and Work Surfaces in Collective Catering Systems in Central Italy: A Five-Year Monitoring Study

Ready-to-eat (RTE) meals produced and served by the catering system still represent one of the major causes of foodborne outbreaks, especially for susceptible consumers. Despite the great progress in food hygiene and safety, the systematic monitoring of microbial contamination of foodstuff is the most effective tool to ensure food safety and protect consumers’ health. The aim of this study was to perform a thorough assessment of the microbial safety and quality of meals and work surfaces of collective catering systems in central Italy, over a five-year period (2014−2018). In total 11,012 microbiological analytical determinations were performed in food matrices (80.1%) and environmental samples (19.9%). The results obtained show a low level of non-conformities ranging from 2.2% to 6.3% of total samples, concerning both hygiene and safety parameters. A decreasing trend of non-conformities during the years was also highlighted (p-value < 0.05), especially for environmental samples. This study suggests that the implementation of Good Manufacturing Practices (GMPs) and the proper definition of Hazard Analysis and Critical Control Point (HACCP) plans, combined with a thorough evaluation of microbiological monitoring, are able to ensure high levels of food safety and hygiene.

Raw Animal Meats as Potential Sources of Clostridium difficile in Al-Jouf, Saudi Arabia

Clostridium difficile present in feces of food animals may contaminate their meats and act as a potential source of C. difficile infection (CDI) to humans. C. difficile resistance to antibiotics, its production of toxins and spores play major roles in the pathogenesis of CDI. This is the first study to evaluate C. difficile prevalence in retail raw animal meats, its antibiotics susceptibilities and toxigenic activities in Al-Jouf, Saudi Arabia. Totally, 240 meat samples were tested. C. difficile was identified by standard microbiological and biochemical methods. Vitek-2 compact system confirmed C. difficile isolates were 15/240 (6.3%). Toxins A/B were not detected by Xpect C. difficile toxin A/B tests. Although all isolates were susceptible to vancomycin and metronidazole, variable degrees of reduced susceptibilities to moxifloxacin, clindamycin or tetracycline antibiotics were detected by Epsilon tests. C. difficile strains with reduced susceptibility to antibiotics should be investigated. Variability between the worldwide reported C. difficile contamination levels could be due to absence of a gold standard procedure for its isolation. Establishment of a unified testing algorithm for C. difficile detection in food products is definitely essential to evaluate the inter-regional variation in its prevalence on national and international levels. Proper use of antimicrobials during animal husbandry is crucial to control the selective drug pressure on C. difficile strains associated with food animals. Investigating the protective or pathogenic potential of non-toxigenic C. difficile strains and the possibility of gene transfer from certain toxigenic/ antibiotics-resistant to non-toxigenic/antibiotics-sensitive strains, respectively, should be worthy of attention.

Prospects for clinical applications of butyrate-producing bacteria

As the major source of energy for colonic mucosal cells and as an important regulator of gene expression, inflammation, differentiation, and apoptosis in host cells, microbiota-derived butyrate can enhance the intestinal mucosal immune barrier, modulate systemic immune response, and prevent infections. Maintaining a certain level of butyrate production in the gut can help balance intestinal microbiota, regulate host immune response, and promote the development and maintenance of the intestinal mucosal barrier. Butyrate-producing bacteria act as probiotics and play important roles in a variety of normal biological functions. Bacteriotherapeutic supplementation by using fecal microbiota transplantation to restore butyrate-producing commensal bacteria in the gut has been very successful in the treatment of recurrent and refractory Clostridium difficile (C. difficile) infection or C. difficile-negative nosocomial diarrhea. Administration of probiotics that include butyrate-producing bacteria may have a role in the treatment of inflammatory bowel diseases and in the prevention of necrotizing enterocolitis and late-onset sepsis in premature infants. Furthermore, modulating gut microbiota with dietary approaches may improve intestinal dysbiosis commonly seen in patients with obesity-associated metabolic disorders. Supplementation with a butyrate-producing bacterial stain might be used to increase energy expenditure, improve insulin sensitivity, and to help control obesity and metabolic syndrome.

<em>Clostridium difficile</em> infection in pediatric patients of oncological hospital: cultivation of anaerobic intestinal flora and treatment

In recent years, the number of infectious diseases caused by Clostridium difficile in the world has grown with a significant increase in relapses and mortality in patients, particularly among the cancer patients in hospitals. There is also observed an increase in the resistance of Clostridium difficile to the first-line drugs, namely metronidazole and vancomycin, which makes the search for new methods of treatment and prevention of this infection even more urgent. In this review, we analyze the recent data on the methods of cultivation and isolation of the pure bacterial culture of Clostridium difficile and other anaerobic enteropathogens over the course of enterocolitis treatment with antimicrobial drugs in pediatric patients with oncopathology. Novel approaches to the therapy of this infection are discussed. 

Characterisation and Antibiotic Susceptibility Profile of Clostridioides (Clostridium) Difficile Isolated from Chicken Carcasses

Introduction

Clostridioides (Clostridium) difficile is a Gram+, anaerobic, spore-forming, rod-shaped bacterium that can produce toxins, and it is mainly because its virulence is attributed. The objective of this study was to evaluate the presence of C. difficile and hyper virulent ribotypes in chicken carcasses and the antibiotic susceptibility of isolated strains.

Material and Methods

C. difficile was isolated from chicken carcasses by microbiological methods, its ribotypes were identified by means of PCR, the toxin production ability was defined by ELISA, and the susceptibility of the isolates to selected antibiotics was determined by minimum inhibitory concentration evaluator strips.

Results

The bacterium was isolated from 69 out of 185 (37.3%) examined chicken carcass samples, and six out of the 69 (8.7%) isolates were identified as ribotype 027. All isolates were susceptible to amoxicillin-clavulanic acid (100.0%), vancomycin (97.1%), metronidazole (88.4%), and tetracycline (95.7%), whereas they were resistant to cefotaxime (97.1%) and imipenem (89.9%).

Conclusion

The results of this study demonstrate the presence of toxigenic C. difficile isolates such as ribotype 027 (one of the most common causes of C. difficile infection in humans) in chicken carcasses. Although there is no case for stating that C. difficile is a food-borne pathogen, the presence of C. difficile in chicken may be considered to be a potential risk to consumers.

Clostridioides (Clostridium) Difficile in Food-Producing Animals, Horses and Household Pets: A Comprehensive Review

Clostridioides (Clostridium) difficile is ubiquitous in the environment and is also considered as a bacterium of great importance in diarrhea-associated disease for humans and different animal species. Food animals and household pets are frequently found positive for toxigenic C. difficile without exposing clinical signs of infection. Humans and animals share common C. difficile ribotypes (RTs) suggesting potential zoonotic transmission. However, the role of animals for the development of human infection due to C. difficile remains unclear. One major public health issue is the existence of asymptomatic animals that carry and shed the bacterium to the environment, and infect individuals or populations, directly or through the food chain. C. difficile ribotype 078 is frequently isolated from food animals and household pets as well as from their environment. Nevertheless, direct evidence for the transmission of this particular ribotype from animals to humans has never been established. This review will summarize the current available data on epidemiology, clinical presentations, risk factors and laboratory diagnosis of C. difficile infection in food animals and household pets, outline potential prevention and control strategies, and also describe the current evidence towards a zoonotic potential of C. difficile infection.

Clostridial Binary Toxins: Basic Understandings that Include Cell Surface Binding and an Internal "Coup de Grâce"

Clostridium species can make a remarkable number of different protein toxins, causing many diverse diseases in humans and animals. The binary toxins of Clostridium botulinum, C. difficile, C. perfringens, and C. spiroforme are one group of enteric-acting toxins that attack the actin cytoskeleton of various cell types. These enterotoxins consist of A (enzymatic) and B (cell binding/membrane translocation) components that assemble on the targeted cell surface or in solution, forming a multimeric complex. Once translocated into the cytosol via endosomal trafficking and acidification, the A component dismantles the filamentous actin-based cytoskeleton via mono-ADP-ribosylation of globular actin. Knowledge of cell surface receptors and how these usurped, host-derived molecules facilitate intoxication can lead to novel ways of defending against these clostridial binary toxins. A molecular-based understanding of the various steps involved in toxin internalization can also unveil therapeutic intervention points that stop the intoxication process. Furthermore, using these bacterial proteins as medicinal shuttle systems into cells provides intriguing possibilities in the future. The pertinent past and state-of-the-art present, regarding clostridial binary toxins, will be evident in this chapter.

Survey, characterization and antimicrobial susceptibility of Clostridium difficile from marine bivalve shellfish of North Adriatic Sea

Clostridium difficile is a major cause of infectious diarrhea associated to healthcare settings. Community-acquired infections are increasingly reported in the last decade and exposure other than to symptomatic patients rather to contaminated foods or animals is feasible. Occurrence of C. difficile in shellfish raises concern because spores can survive the cooking temperatures given that shellfish is often consumed poorly cooked or raw. Aim of our study was to investigate whether shellfish represents a reservoir of C. difficile human PCR-ribotypes (RTs). 702 shellfish samples of farmed and wild bivalve mollusc species were collected over the 2015-2017 period in North Adriatic Italian Sea to investigate contamination with C. difficile and characterize the isolates in terms of genotypic variability and antimicrobial resistance profile. C. difficile was detected in 16.9% (CI: 14.1%-19.8%) samples: 11.6% mussels and 23.2% clams. Compared to mussels, clams were significantly associated with detection of C. difficile (OR = 2.4, P < 0.01). Overall 113 C. difficile isolates were genotyped and 75 (66.4%) were toxigenic. Fifty-three different RTs were identified. 40.7% C. difficile isolates were among the RTs most commonly involved in human infection in Europe. The profile of antimicrobial susceptibility was determined by E-test; microbiological resistance was frequent against clindamycin (17%), erythromycin (23%), rifampicin (8.8%) and moxifloxacin (10.6%). All isolates were susceptible to metronidazole and one showed MIC > ECOFF for vancomycin. C. difficile strains showed high variety in RTs, most of them already detected in other animals or known as highly virulent and epidemic in humans. These results prompt towards investigating on specific risk mitigation measures against C. difficile and are preliminary for any source attribution and risk assessment study.

Prevalence of Clostridium difficile Isolated from Beef and Chicken Meat Products in Turkey

The concern about the possibility of food can be a vehicle for the transmission of Clostridium difficile to humans has been raised recently due to the similarities among the strains isolated from patients, foods and food animals. In this study, therefore, the prevalence of C. difficile was investigated in beef and chicken meat products collected from 57 different butcher shops, markets and fast food restaurants in Sakarya province of Turkey. Two out of 101 samples (1.98%) was positive for C. difficile indicating a very low prevalence. The pathogen was isolated from an uncooked meatball sample and a cooked meat döner sample, whereas not detected in chicken meat samples. The meatball isolate was resistant to vancomycin and tetracycline, while the cooked meat döner isolate was resistant to vancomycin and metronidazole. Both isolates were sensitive to moxifloxacin and clindamycin. Toxins A and B were not detected. This study reveals the presence of C. difficile in further processed beef products in Turkey.

Novel Clade C-I Clostridium difficile strains escape diagnostic tests, differ in pathogenicity potential and carry toxins on extrachromosomal elements

The population structure of Clostridium difficile currently comprises eight major genomic clades. For the highly divergent C-I clade, only two toxigenic strains have been reported, which lack the tcdA and tcdC genes and carry a complete locus for the binary toxin (CDT) next to an atypical TcdB monotoxin pathogenicity locus (PaLoc). As part of a routine surveillance of C. difficile in stool samples from diarrheic human patients, we discovered three isolates that consistently gave negative results in a PCR-based screening for tcdC. Through phenotypic assays, whole-genome sequencing, experiments in cell cultures, and infection biomodels we show that these three isolates (i) escape common laboratory diagnostic procedures, (ii) represent new ribotypes, PFGE-types, and sequence types within the Clade C-I, (iii) carry chromosomal or plasmidal TcdBs that induce classical or variant cytopathic effects (CPE), and (iv) cause different levels of cytotoxicity and hamster mortality rates. These results show that new strains of C. difficile can be detected by more refined techniques and raise questions on the origin, evolution, and distribution of the toxin loci of C. difficile and the mechanisms by which this emerging pathogen causes disease.

Antimicrobial Effect of Asiatic Acid Against Clostridium difficile Is Associated With Disruption of Membrane Permeability

Antibiotic resistance is a major concern in Clostridium difficile, the causative agent of antibiotic-associated diarrhea. Reduced susceptibility to first- and second-line agents is widespread, therefore various attempts have been made to seek alternative preventive and therapeutic strategies against this pathogen. In this work, the antimicrobial properties of asiatic acid were evaluated against C. difficile. Asiatic acid displayed substantial inhibitory effects on 19 C. difficile isolates collected from different sources with minimal inhibitory concentrations ranging from 10 to 20 μg/ml. Time kill analysis and minimal bactericidal concentration revealed potential bactericidal activity of this compound. Asiatic acid induced membrane damages and alterations in morphological ultrastructure in C. difficile, thereby causing the leakage of intracellular substances. Moreover, asiatic acid also displayed an inhibitory effect on cell motility, but did not interfere with biofilm formation and spore germination. Analysis of drug combination showed no synergistic effect between asiatic acid and vancomycin/metronidazole. Altogether, asiatic acid exhibited strong antimicrobial activity against vegetative cells and could serve as an alternative resource for tackling C. difficile.

In silico identification of molecular mimics involved in the pathogenesis of Clostridium botulinum ATCC 3502 strain

Bacterial pathogens invade and disrupt the host defense system by means of protein sequences structurally similar at global and local level both. The sharing of homologous sequences between the host and the pathogenic bacteria mediates the infection and defines the concept of molecular mimicry. In this study, various computational approaches were employed to elucidate the pathogenicity of Clostridium botulinum ATCC 3502 at genome-wide level. Genome-wide study revealed that the pathogen mimics the host (Homo sapiens) and unraveled the complex pathogenic pathway of causing infection. The comparative 'omics' approaches helped in selective screening of 'molecular mimicry' candidates followed by the qualitative assessment of the virulence potential and functional enrichment. Overall, this study provides a deep insight into the emergence and surveillance of multidrug resistant C. botulinum ATCC 3502 caused infections. This is the very first report identifying C. botulinum ATCC 3502 proteome enriched similarities to the human host proteins and resulted in the identification of 20 potential mimicry candidates, which were further characterized qualitatively by sub-cellular organization prediction and functional annotation. This study will provide a variety of avenues for future studies related to infectious agents, host-pathogen interactions and the evolution of pathogenesis process.

Bacillus spp. as direct-fed microbial antibiotic alternatives to enhance growth, immunity, and gut health in poultry

The increasing occurrence of antibiotic-resistant bacteria combined with regulatory pressure and consumer demands for foods produced without antibiotics has caused the agricultural industry to restrict its practice of using antibiotic growth promoters (AGP) in food animals. The poultry industry is not immune to this trend, and has been actively seeking natural alternatives to AGP that will improve the health and growth performance of commercial poultry flocks. Bacillus probiotics have been gaining in popularity in recent years as an AGP alternative because of their health-promoting benefits and ability to survive the harsh manufacturing conditions of chicken feed production. This review provides an overview of several modes of action of some Bacillus direct-fed microbials as probiotics. Among the benefits of these direct-fed microbials are their production of naturally synthesized antimicrobial peptides, gut flora modulation to promote beneficial microbiota along the gastrointestinal tract, and various immunological and gut morphological alterations. The modes of action for increased performance are not well defined, and growth promotion is not equal across all Bacillus species or within strains. Appropriate screening and characterization of Bacillus isolates prior to commercialization are necessary to maximize poultry growth to meet the ultimate goal of eliminating AGP usage in animal husbandry.

Norovirus and Clostridium difficile outbreaks: squelching the wildfire

PURPOSE OF REVIEW

Gastrointestinal outbreaks in the healthcare setting cause increased morbidity and mortality in an already vulnerable population. Optimization of infection prevention measures can be a challenge in healthcare settings. This review describes new literature that may change the traditional infection prevention approach to such outbreaks.

RECENT FINDINGS

Asymptomatic carriers of both norovirus and Clostridium difficile can pose risk of transmission to others and the environment. Rapid recognition and diagnosis can decrease the extent of an outbreak. No-touch technologies for environmental disinfection are new and effective tools. Infection prevention consultant services and systems redesign can augment efforts to control baseline infection rates and outbreaks. Antimicrobial stewardship continues to be essential to prevent C. difficile infection.

SUMMARY

New approaches are needed to stem the tide of norovirus and C. difficile clusters and outbreaks in healthcare settings. Accurate recognition, testing, and implementation of infection prevention measures can be supported with rapid testing modalities, access to updated guidelines and no-touch disinfection systems. The work-environment culture should be carefully assessed and restructured using human engineering models to promote effective infection prevention practices. Antimicrobial stewardship initiatives are needed at the bedside and at national levels.

Clostridium difficile infection: Evolution, phylogeny and molecular epidemiology

Over the recent decades, Clostridium difficile infection (CDI) has emerged as a global public health threat. Despite growing attention, C. difficile remains a poorly understood pathogen, however, the exquisite sensitivity offered by next generation sequencing (NGS) technology has enabled analysis of the genome of C. difficile, giving us access to massive genomic data on factors such as virulence, evolution, and genetic relatedness within C. difficile groups. NGS has also demonstrated excellence in investigations of outbreaks and disease transmission, in both small and large-scale applications. This review summarizes the molecular epidemiology, evolution, and phylogeny of C. difficile, one of the most important pathogens worldwide in the current antibiotic resistance era.

Survival of Clostridium difficile spores at low water activity

Clostridium difficile is frequently found in meat and meat products. Germination efficiency, defined as colony formation, was previously investigated at temperatures found in meat handling and processing for spores of strain M120 (animal isolate), R20291 (human isolate), and DK1 (beef isolate). In this study, germination efficiency of these spore strains was assessed in phosphate buffered saline (PBS, a_w ∼1.00), commercial beef jerky (a_w ∼0.82/0.72), and a_w-adjusted PBS (a_w ∼0.82/0.72). Surface hydrophobicity was followed for spores stored in PBS. After three months and for all PBS a_w levels tested, M120 and DK1 spores showed a ∼1 decimal reduction in colony formation but this was not the case when kept in beef jerky suggesting a protective food matrix effect. During storage, and with no significant a_w effect, an increase in colony formation was observed for R20291 spores kept in PBS (∼2 decimal log increase) and beef jerky (∼1 decimal log increase) suggesting a loss of spore superdormancy. For all strains, no significant changes in spore surface hydrophobicity were observed after storage. Collectively, these results indicate that depending on the germination properties of C. difficile spores and the media properties, their germination efficiency may increase or decrease during long term food storage.

Antibiotic Treatment of Hospitalized Patients with Pneumonia Complicated by Clostridium Difficile Infection

Clostridium difficile infection (CDI) is one of the most common gastrointestinal complication after antimicrobial treatment. It is estimated that CDI after pneumonia treatment is connected with a higher mortality than other causes of hospitalization. The aim of the study was to assess the relationship between the kind of antibiotic used for pneumonia treatment and mortality from post-pneumonia CDI. We addressed the issue by examining retrospectively the records of 217 patients who met the diagnostic criteria of CDI. Ninety four of those patients (43.3 %) came down with CDI infection after pneumonia treatment. Fifty of the 94 patients went through severe or severe and complicated CDI. The distribution of antecedent antibiotic treatment of pneumonia in these 50 patients was as follows: ceftriaxone in 14 (28 %) cases, amoxicillin with clavulanate in 9 (18 %), ciprofloxacin in 8 (16.0 %), clarithromycin in 7 (14 %), and cefuroxime and imipenem in 6 (12 %) each. The findings revealed a borderline enhancement in the proportion of deaths due to CDI in the ceftriaxone group compared with the ciprofloxacin, cefuroxime, and imipenem groups. The corollary is that ceftriaxone should be shunned in pneumonia treatment. The study demonstrates an association between the use of a specific antibiotic for pneumonia treatment and post-pneumonia mortality in patients who developed CDI.

An Evaluation of Food as a Potential Source for Clostridium difficile Acquisition in Hospitalized Patients

OBJECTIVE To determine whether Clostridium difficile is present in the food of hospitalized patients and to estimate the risk of subsequent colonization associated with C. difficile in food. METHODS This was a prospective cohort study of inpatients at a university-affiliated tertiary care center, May 9, 2011-July 12, 2012. Enrolled patients submitted a portion of food from each meal. Patient stool specimens and/or rectal swabs were collected at enrollment, every 3 days thereafter, and at discharge, and were cultured for C. difficile. Clinical data were reviewed for evidence of infection due to C. difficile. A stochastic, discrete event model was developed to predict exposure to C. difficile from food, and the estimated number of new colonization events from food exposures per 1,000 admissions was determined. RESULTS A total of 149 patients were enrolled and 910 food specimens were obtained. Two food specimens from 2 patients were positive for C. difficile (0.2% of food samples; 1.3% of patients). Neither of the 2 patients was colonized at baseline with C. difficile. Discharge colonization status was available for 1 of the 2 patients and was negative. Neither was diagnosed with C. difficile infection while hospitalized or during the year before or after study enrollment. Stochastic modeling indicated contaminated hospital food would be responsible for less than 1 newly colonized patient per 1,000 hospital admissions. CONCLUSIONS The recovery of C. difficile from the food of hospitalized patients was rare. Modeling suggests hospital food is unlikely to be a source of C. difficile acquisition. Infect Control Hosp Epidemiol 2016;1401-1407.

Clostridium difficile environmental contamination within a clinical laundry facility in the USA

Clostridium difficile is both a hospital and community-acquired pathogen. The current study determined if C. difficile could be cultured from clinical laundry facility surfaces. A total of 240 surface samples were collected from dirty areas (n = 120), which handle soiled clinical linens, and from clean areas (n = 120), which process and fold the clean linens, within the University of Washington Consolidated Laundry facility in 2015. Sampling was done four times over the course of 1 year. The dirty area was significantly more contaminated than the clean area (21% vs 2%, P < 0.001). Clostridium difficile isolates were genetically characterized using multilocus sequence typing and PCR for the detection of genes encoding toxin A and toxin B. The MLST types 1, 2, 3, 15, 26, 34, 35, 39, 42, 43, 44, 53, 63 and 284 were identified and have previously been found in both clinical and community settings. Toxin positive isolates were identified in both the dirty (n = 16/25) and clean areas (n = 2/2). Seasonal variation was observed with 40% of the 27 isolates cultured in April 2015. The study suggests that soiled clinical linens may be a source of C. difficile surface contamination.

Clostridium difficile Infection in Production Animals and Avian Species: A Review

Clostridium difficile is the leading cause of antibiotic-associated diarrhea and colitis in hospitalized humans. Recently, C. difficile infection (CDI) has been increasingly recognized as a cause of neonatal enteritis in food animals such as pigs, resulting in stunted growth, delays in weaning, and mortality, as well as colitis in large birds such as ostriches. C. difficile is a strictly anaerobic spore-forming bacterium, which produces two toxins A (TcdA) and B (TcdB) as its main virulence factors. The majority of strains isolated from animals produce an additional binary toxin (C. difficile transferase) that is associated with increased virulence. C. difficile is ubiquitous in the environment and has a wide host range. This review summarizes the epidemiology, clinical presentations, risk factors, and laboratory diagnosis of CDI in animals. Increased awareness by veterinarians and animal owners of the significance of clinical disease caused by C. difficile in livestock and avians is needed. Finally, this review provides an overview on methods for controlling environmental contamination and potential therapeutics available.

Thermal Resistance of Clostridium difficile Spores in Peptone Water and Pork Meat

The thermal resistance of four strains of Clostridium difficile spores (three hypervirulent and one nonhypervirulent) in peptone water (PW) and pork meat was evaluated individually at 70, 75, 80, 85, and 90°C using two recovery methods (taurocholate and lysozyme). PW or meat was inoculated with C. difficile spores and mixed to obtain ca. 5.0 log CFU/ml or 4.0 log CFU/g, respectively. The D-values of C. difficile spores in PW ranged from 7.07 to 22.14 h, 1.42 to 3.82 h, 0.35 to 0.59 h, 4.93 to 5.95 min, and 1.16 to 1.76 min at 70, 75, 80, 85, and 90°C, respectively, for the four strains using the taurocholate method. The D-values of the respective C. difficile spores were greater (P ≤ 0.05) using the lysozyme method, especially at higher temperatures (85 and 90°C). Greater thermal resistance of C. difficile spores was observed in meat than in PW using the lysozyme method. Hypervirulence of the C. difficile strains was not associated with greater thermal resistance in meat. The z-values for C. difficile spores in meat were between 6.21 and 7.21°C, and they were 11.24 and 12.12°C using the taurocholate and the lysozyme recovery methods, respectively. The D- and z-values of C. difficile spores were greater in both PW and pork than the values reported in the literature. C. difficile spores can survive traditional cooking or thermal processing practices and potentially grow in cooked, ready-to-eat products. The use of effective methods to recover heat-injured spores is necessary to obtain accurate thermal destruction parameters for C. difficile spores.

Clostridium difficile in Food and Animals: A Comprehensive Review

Zoonoses are infections or diseases that can be transmitted between animals and humans through direct contact, close proximity or the environment. Clostridium difficile is ubiquitous in the environment, and the bacterium is able to colonise the intestinal tract of both animals and humans. Since domestic and food animals frequently test positive for toxigenic C. difficile, even without showing any signs of disease, it seems plausible that C. difficile could be zoonotic. Therefore, animals could play an essential role as carriers of the bacterium. In addition, the presence of the spores in different meats, fish, fruits and vegetables suggests a risk of foodborne transmission. This review summarises the current available data on C. difficile in animals and foods, from when the bacterium was first described up to the present.