Hydroponic Nutrient Solution Temperature Impacts Tulane Virus Persistence over Time

Controlled environment agriculture (CEA), or indoor agriculture, encompasses non-traditional farming methods that occur inside climate-controlled structures (e.g., greenhouses, warehouses, high tunnels) allowing for year-round production of fresh produce such as leaf lettuce. However, recent outbreaks and recalls associated with hydroponically grown lettuce contaminated with human pathogens have raised concerns. Few studies exist on the food safety risks during hydroponic cultivation of leaf lettuce; thus, it is important to identify contributing risk factors and potential mitigation strategies to prevent foodborne transmission via hydroponically grown produce. In this study, the concentration of infectious Tulane virus (TV), a human norovirus surrogate, in hydroponic nutrient solution at 15 °C, 25 °C, 30 °C, and 37 °C was determined over a duration of 21 days to mimic the time from seedling to mature lettuce. The mean log PFU reduction for TV was 0.86, 1.80, 2.87, and ≥ 3.77 log10 at 15 °C, 25 °C, 30 °C, and 37 °C, respectively, at the end of the 21-day period. Similarly, average decimal reduction values (D-values) of TV at 15 °C, 25 °C, 30 °C, and 37 °C were 48.0, 11.3, 8.57, and 7.02 days, respectively. This study aids in the (i) identification of possible food safety risks associated with hydroponic systems specifically related to nutrient solution temperature and (ii) generation of data to perform risk assessments within CEA leaf lettuce operations to inform risk management strategies for the reduction of foodborne outbreaks, fresh produce recalls, and economic losses.

A comprehensive examination of microbial hazards and risks during indoor soilless leafy green production

Produce grown under controlled environment agriculture (CEA) is often assumed to have a reduced risk of pathogen contamination due to the low chance of exposure to outdoor contaminant factors. However, the 2021 outbreak and numerous recalls of CEA-grown lettuce and microgreens demonstrate the possibility of pathogen introduction during indoor production when there is a failure in the implementation of food safety management systems. Indoor production of commercial leafy greens, such as lettuce and microgreens, is performed across a range of protective structures from primitive household setups to advanced and partially automatized growing systems. Indoor production systems include hydroponic, aquaponic, and aeroponic configurations. Hydroponic systems such as deep water culture and nutrient film technique comprised of various engineering designs represent the main system types used by growers. Depending on the type of leafy green, the soilless substrate, and system selection, risk of microbial contamination will vary during indoor production. In this literature review, science-based pathogen contamination risks and mitigation strategies for indoor production of microgreens and more mature leafy greens are discussed during both pre-harvest and post-harvest stages of production.

Post-acute sequelae of SARS-CoV-2 (PASC) in nursing home residents: A retrospective cohort study

BACKGROUND

Post-acute sequelae of SARS-CoV-2 (PASC) describes a syndrome of physical and cognitive decline that persists after acute symptoms of infection resolve. Few studies have explored PASC among nursing home (NH) residents.

METHODS

A retrospective cohort study was conducted at two NHs in Michigan. COVID-positive patients were identified from March 21, 2020 to October 26, 2021. The comparison group were patients who lived at the same NH but who were never infected during the study period. Minimum Data Set was used to examine trajectories of functional dependence (Activity of Daily Living [ADL] composite score) and cognitive function (Brief Interview for Mental Status [BIMS]). Linear mixed-effects models were constructed to estimate short-term change in function and cognition immediately following diagnosis and over time for an additional 12 months, compared to pre-COVID and non-COVID trajectories and adjusting for sex, age, and dementia status.

RESULTS

We identified 171 residents (90 COVID-19 positive, 81 non-COVID) with 719 observations for our analyses. Cohort characteristics included: 108 (63%) ≥ 80 yrs.; 121 (71%) female; 160 (94%) non-Hispanic white; median of 3 comorbidities (IQR 2-4), with no significant differences in characteristics between groups. COVID-19 infection affected the trajectory of ADL recovery for the first 9 months following infection, characterized by an immediate post-infection decrease in functional status post-infection (-0.60 points, p = 0.002) followed by improvement toward the expected functional trajectory sans infection (0.04 points per month following infection, p = 0.271).

CONCLUSIONS

NH residents experienced a significant functional decline that persisted for 9 months following acute infection. Further research is needed to determine whether increased rehabilitation services after COVID-19 may help mitigate this decline.

Does high school health education class satisfaction influence student perceptions of public health and pandemic response?

BACKGROUND

The COVID-19 pandemic significantly affected high school students. Little is known about the mediators of student perceptions of infection prevention and public health entities. We piloted a survey to evaluate the relationship between student perceptions of COVID-19 topics and satisfaction with their most recent health class.

METHODS

Students from one private high school in southeast Michigan completed a survey in early 2022. The primary outcomes were 4 domains: vaccination knowledge, intervention effectiveness, intervention impact, and willingness to readopt an intervention. We assessed the associations between health class satisfaction and these outcomes using multiple linear regression.

RESULTS

One-hundred ninety students reported their health class satisfaction and were eligible for analysis. Students reported high confidence in vaccines (93%) but limited knowledge of COVID-19 vaccination (45%). Students perceived COVID-19 interventions as highly effective (range, 72% [hand hygiene]-93% [vaccination]) and reported a willingness to readopt them (range, 73% [stay-at-home orders]-96% [vaccination]). Health class satisfaction (54%) was positively associated with composite scores on vaccination knowledge and intervention effectiveness.

DISCUSSION

Assessing students' intrapandemic perspectives on infection prevention illuminated areas of strength (ie, intervention confidence) and areas for improvement (ie, intervention knowledge and institutional confidence).

CONCLUSIONS

Students reported favorable perceptions regarding common infection prevention interventions. Future work should investigate the role of educational satisfaction in mediating confidence in public health interventions and institutions.

From bytes to bites: Advancing the food industry with three-dimensional food printing

The rapid advancement of three-dimensional (3D) printing (i.e., a type of additive manufacturing) technology has brought about significant advances in various industries, including the food industry. Among its many potential benefits, 3D food printing offers a promising solution to deliver products meeting the unique nutritional needs of diverse populations while also promoting sustainability within the food system. However, this is an emerging field, and there are several aspects to consider when planning for use of 3D food printing for large-scale food production. This comprehensive review explores the importance of food safety when using 3D printing to produce food products, including pathogens of concern, machine hygiene, and cleanability, as well as the role of macronutrients and storage conditions in microbial risks. Furthermore, postprocessing factors such as packaging, transportation, and dispensing of 3D-printed foods are discussed. Finally, this review delves into barriers of implementation of 3D food printers and presents both the limitations and opportunities of 3D food printing technology.

Cultivating Food Safety Together: Insights About the Future of Produce Safety in the U.S. Controlled Environment Agriculture Sector

Controlled environment agriculture (CEA) is a rapidly growing sector that presents unique challenges and opportunities in ensuring food safety. This manuscript highlights critical gaps and needs to promote food safety in CEA systems as identified by stakeholders (n=47) at the Strategizing to Advance Future Extension andResearch (S.A.F.E.R.) CEA conference held in April 2023 at The Ohio State University's Ohio CEA Research Center. Feedback collected at the conference was analyzed using an emergent thematic analysis approach to determine key areas of focus. Research-based guidance is specific to the type of commodity, production system type, and size. Themes include the need for improved supply chain control, cleaning, and sanitization practices, pathogen preventive controls and mitigation methods and training and education. Discussions surrounding supply chain control underscored the significance of the need for approaches to mitigate foodborne pathogen contamination. Effective cleaning and sanitization practices are vital to maintaining a safe production environment, with considerations such as establishing standard operating procedures, accounting for hygienic equipment design, and managing the microbial communities within the system. Data analysis further highlights the need for risk assessments, validated pathogen detection methods, and evidence-based guidance in microbial reduction. In addition, training and education were identified as crucial in promoting a culture of food safety within CEA. The development of partnerships between industry, regulatory, and research institutions are needed to advance data-driven guidance and practices across the diverse range of CEA operations and deemed essential for addressing challenges and advancing food safety practices in CEA. Considering these factors, the CEA industry can enhance food safety practices, foster consumer trust, and support its long-term sustainability.

Growing Safer Greens: Exploring Food Safety Practices and Challenges in Indoor, Soilless Production Through Thematic Analysis of Leafy Greens Grower Interviews

Indoor, soilless production-often referred to more broadly as controlled environment agriculture (CEA)-is increasingly used for the cultivation of leafy greens. Minimal information is currently available regarding food safety practices during production and distribution of leafy greens grown within indoor, soilless environments in the United States (U.S.). This study aimed to describe production challenges and implementation of good agricultural practices among CEA growers. Data collection methods included semi-structured interviews (N = 25) and a supplemental online survey completed by growers (N = 12) in the U.S. Out of 18 total responses (i.e., multiple responses allowed per completed survey), survey data indicated that lettuce (n = 5; 27.8%) was the most commonly grown leafy green, followed by culinary herbs (n = 3; 16.7%) and arugula (n = 3; 16.7%). Most growers (n = 7; 58.3%) grew other agricultural products, specifically other crops in addition to leafy greens. Revenue from sales ranged from US$500 000 per year. Meanwhile, nearly half (n = 5; 45.5%) of respondents (N = 11) were uncertain whether their produce was subject to the FSMA Produce Safety Rule. Most survey respondents used vertical farming techniques (5 out of 11; 45.5%) or some variety of greenhouse (4 out of 11; 36.4%). Based on 35 total responses, leafy greens were most commonly sold to "Commercial Restaurants" (n = 7; 20.0%), "Grocery Stores" (n = 7; 20.0%), "Institutional Foodservice Establishments (hospitals, schools, childcare, long-term care)" (n = 6; 17.1%), and "Wholesaler/Distributers" (n = 6; 17.1%). The 11 interview questions elucidated three major themes: contextual, barriers to risk management and regulatory compliance, and research needs. Thirteen subthemes were identified, and an example of a subtheme within each major theme, respectively, includes worker hygiene and training, regulatory and certification environment, and risk assessments of individual issues.

Aqueous Ozone Efficacy for Inactivation of Foodborne Pathogens on Vegetables Used in Raw Meat-Based Diets for Companion Animals

The present study evaluates the efficacy of a batch wash ozone sanitation system (BWOSS) and spray wash ozone sanitation system (SWOSS) against Listeria monocytogenes (two strains) and Salmonella enterica subsp. enterica (three serovars) inoculated on the surface of carrots, sweet potatoes, and butternut squash, commonly used in raw meat-based diets (RMBDs) marketed for companion animals such as dogs and cats. Produce either remained at room temperature for 2 h or were frozen at -20°C and then tempered overnight at 4°C to mimic the preprocessing steps of a raw pet food processing operation ('freeze-temper') prior to ozone treatment. Two ozone concentrations (0 and 5 ppm) were applied for either 20 s or 60 s for BWOSS and 20 s for SWOSS. Based on an ANOVA, BWOSS data showed no significant difference (P > 0.05) in microbial reduction between 0 and 5 ppm ozone concentration across all treatment durations for each produce type. BWOSS resulted in mean microbial reductions of up to 1.56 log CFU/mL depending on the treatment time and produce type. SWOSS data were analyzed using a generalized linear model with Quasipoisson errors. Freeze-tempered produce treated with SWOSS had a higher bacterial log reduction at 5 ppm ozone compared to 0 ppm ozone (P = 0.0013) whereas room temperature produce treated with SWOSS did not show any significant difference in microbial reduction between ozone concentrations. The potential to mitigate microbial cross-contamination was also investigated during SWOSS treatment. The results indicate that 5 ppm ozone decreased pathogens in the rinsate and proximal surfaces by 0.63-1.66 log CFU/mL greater than no ozone depending on the pathogen and sample. Overall, data from this study indicate that SWOSS would be more effective compared to BWOSS in reducing the microbial load present on the surface of root tubers and squash subjected to freezing and thawing and has the potential to mitigate cross-contamination within RMDB manufacturing environments.

Persistence of Salmonella enterica subsp. enterica ser. Javiana, Listeria monocytogenes, and Listeria innocua in Hydroponic Nutrient Solution

This study aimed to determine the persistence of Salmonella Javiana, Listeria monocytogenes, and Listeria innocua in nonsterile, hydroponic nutrient solution (NS) at 15, 25, 30, and 37°C over a 21-day period to mimic time from seedling to mature lettuce. Bacteria were inoculated in modified Hoagland's NS at 106 CFU/mL and maintained at 15, 25, 30, and 37°C. Samples were collected at various time points, and bacteria were quantified. A mixed model was used to determine the effect of bacteria type, time (day), and temperature on bacteria concentration (log CFU/mL). The least-squares means were calculated to compare the mean log CFU/mL, and the mean values were compared with Tukey-Kramer honest significant difference test with a significance level of P = 0.05. Statistical analysis indicated that a 3-way interaction effect between temperature, time, and bacteria type had a significant impact on bacterial persistence in NS (P < 0.0001). At all temperatures, S. Javiana persisted in NS throughout the 21-day study period, compared to L. innocua and L. monocytogenes where persistence was limited to between 1 and 14 days. Similarly, decimal reduction values (D-values) of S. Javiana indicated longer persistence in NS than L. innocua and L. monocytogenes at most temperatures. For instance, at 15°C and 25°C, D-values for S. Javiana were estimated at 82 and 26 d, respectively, compared to D-values of 3.6 and ∼3 d for L. monocytogenes. Data indicate that the temperature of NS has a differential effect on the persistence of S. Javiana and Listeria spp. This study furthers the understanding of potential food safety risks associated with hydroponic systems and will contribute to the refinement of further studies to aid in the development of operation-specific risk profiles.

Transfer rates of Salmonella Typhimurium, Listeria monocytogenes, and a human norovirus surrogate impacted by macronutrient composition of food inks in 3D food printing systems

3D food printers (3DFPs) allow for the customization of the physiochemical properties of foods in new ways. Transfer kinetics of foodborne pathogens between surfaces and food inks have not been evaluated in 3DFPs. This study aimed to determine if the macromolecular composition of food inks would impact the transfer rate of foodborne pathogens from the stainless steel food ink capsule to the 3D printed food. Salmonella Typhimurium, Listeria monocytogenes, and a human norovirus surrogate, Tulane virus (TuV), were inoculated onto the interior surface of stainless steel food ink capsules and dried for 30 min. Subsequently, 100 g of one of the following prepared food inks was extruded: (1) pure butter, (2) a powdered sugar solution, (3) a protein powder solution, and (4) a 1:1:1 ratio of all three macromolecules. Pathogen enumeration was completed for both the soiled capsules and the printed food products and resulting transfer rates were estimated using a generalized linear model with quasibinomial errors. A significant two-way interaction effect was found between microorganism type and food ink type (P = 0.0002). Tulane virus was typically transferred the most, and no significant differences between L. monocytogenes and S. Typhimurium were observed for any food matrix or across food matrices. Among food matrices, the complex mixture transferred fewer microorganisms in all instances, while butter, protein, and sugar were all statistically indistinguishable. This research seeks to further develop the field of 3DFP safety and to advance the understanding of the role of macromolecular composition in pathogen transfer kinetics, which have not previously been explored in pure matrices.

Surface Inactivation of a SARS-CoV-2 Surrogate with Hypochlorous Acid is Impacted by Surface Type, Contact Time, Inoculum Matrix, and Concentration

Indirect contact with contaminated surfaces is a potential transmission route for COVID-19. Therefore, it is necessary to investigate convenient and inexpensive surface sanitization methods, such as HOCl, against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The SARS-CoV-2 surrogate, Phi6 (~ 7 log PFU/mL), was prepared in artificial saliva and tripartite matrices, spot inoculated on coupons of either stainless steel or vinyl, and allowed to dry. The coupons were sprayed with either 500 ppm or 1000 ppm HOCl, and remained on the surface for 0 s (control), 5 s, 30 s, or 60 s. Samples were enumerated via the double agar overlay assay. Statistical analysis was completed in R using a generalized linear model with Quasipoisson error approximations. Time, concentration, surface type, and inoculum matrix were all significant contributors to log reduction at P = 0.05. Significant three-way interactions were observed for 1000 ppm, vinyl, and 60 s (P = 0.03) and 1000 ppm, tripartite, and 60 s (P = 0.0121). A significant two-way interaction between vinyl and 60 s was also observed (P = 0.0168). Overall, increased HOCl concentration and exposure time led to increased Phi6 reduction. Notably, the highest estimated mean log reduction was 3.31 (95% CI 3.14, 3.49) for stainless steel at 60 s and 1000 ppm HOCl in artificial saliva, indicating that this method of sanitization may not adequately reduce enveloped viruses to below infective thresholds.

Diversity and Persistence of MRSA and VRE in Skilled Nursing Facilities: Environmental Screening, Whole Genome Sequencing, Development of a Dispersion Index

BACKGROUND

Environmental contamination with methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE) in skilled nursing facilities (SNFs) may contribute to patient acquisition. We assessed diversity and association of MRSA and VRE isolates in a SNF wing and developed a mathematical index to define each strain's tendency to persist in rooms and spread horizontally.

METHODS

Longitudinal study of MRSA and VRE colonization and contamination among successive patient occupancies in a cluster of nine SNF private rooms during eight months characterized by microbiological testing and whole genome isolate typing. 'Dispersion index" of a strain is defined as the number of rooms it was found in (including the patient), divided by the average of times it was found consecutively in the same room.

FINDINGS

MRSA (ten strain types) and VRE (seven types) were recovered from room or patient in 16.4% and 35.6% of the occupancies, respectively. MRSA showed moderate horizontal spread and several episodes of same-room persistence (three distinct strain types) (overall dispersion index: 1.08). VRE showed high tendency towards horizontal spread /new introductions (overall dispersion index: 3.25), and only one confirmed persistence episode.

INTERPRETATION

The emerging picture of high diversity among contaminating strains and high likelihood of room persistence despite terminal cleaning (MRSA) and horizontal spread between rooms (VRE) in this setting calls for improved cleaning practices, heightened contact precautions, and most of all to establish individually tailored facility screening programs to enable informed choices based on local, measurable and actionable epidemiologic parameters.

FUNDING

University of Michigan OAIC REC Scholarship to M.C. National Institutes of Health K24 AG050685 to L.M.

Microgreen Variety Impacts Leaf Surface Persistence of a Human Norovirus Surrogate

Human norovirus (HuNoV) is a pathogenic agent that is frequently associated with foodborne disease outbreaks linked to fresh produce. Within microgreen production systems, understanding of virus transmission routes and persistence is limited. To investigate virus persistence on microgreen leaf surfaces, this study mimicked virus contaminations caused during microgreen handling by farm workers or during overhead irrigation with contaminated water. Specifically, approximately 5 log PFU of Tulane virus (TV)-a HuNoV surrogate-was inoculated on sunflower (SF) and pea shoot (PS) microgreen leaves at 7-day age. The virus reduction on SF was significantly higher than PS (p < 0.05). On day 10, total TV reduction for SF and PS were 3.70 ± 0.10 and 2.52 ± 0.30 log PFU/plant, respectively. Under the environmental scanning electron microscope (ESEM) observation, the leaf surfaces of SF were visually smoother than PS, while their specific effect on virus persistence were not further characterized. Overall, this study revealed that TV persistence on microgreen leaves was plant variety dependent. In addition, this study provided a preliminary estimation on the risk of HuNoV contamination in a microgreen production system which will aim the future development of prevention and control measures.

Performance of Manufacturer Cleaning Recommendations Applied to 3D Food Ink Capsules for the Control of a Human Norovirus Surrogate

With the widespread availability of 3D food printing systems for purchase, users can customize their food in new ways. Manufacturer recommendations for cleaning these machines remain untested with regard to the prevention of foodborne pathogen transmission. This study aimed to determine if manufacturer cleaning recommendations for food ink capsules utilized in 3D food printers are adequate to control human norovirus (HuNoV). A HuNoV surrogate, Tulane virus (TuV; ~ 6 log₁₀ PFU/mL), was inoculated onto the interior surface of stainless steel food ink capsules. Capsules were either unsoiled or soiled with one of the following: butter, protein powder solution, powdered sugar solution, or a mixture containing all three food components. The capsules were allowed to dry and then one of three hygienic protocols was applied: manual washing (MW), a dishwasher speed cycle (DSC), or a dishwasher heavy cycle (DHC). The interaction effect between DSC and pure butter was a significant predictor of log reduction (P = 0.0067), with the pure butter and DSC combination achieving an estimated mean log reduction of 4.83 (95% CI 4.13, 5.59). The DSC was the least effective method of cleaning when compared with MW and the DHC. The 3-way interaction effects between wash type, soil, and capsule position were a significant predictor of log reduction (P = 0.00341). Capsules with butter in the DSC achieved an estimated mean log reduction of 2.81 (95% CI 2.80, 2.83) for the front-most position versus 6.35 (95% CI 6.33, 6.37) for the back-most position. Soil matrix, cleaning protocol, and capsule position all significantly impact capsule cleanability and potential food safety risk. The DHC is recommended for all capsules, and the corners should be avoided when placing capsules into the dishwasher. The current study seeks to provide recommendations for users of additive manufacturing and 3D food printing including consumers, restaurants, industry, and regulatory industries.

Persistence and transfer of Tulane virus in a microgreen cultivation system

Microgreens are niche salad greens which have increased in popularity among consumers in recent years. Due to similarities with sprouts and leafy greens-both attributed to numerous foodborne disease outbreaks-characterization of the food safety risks associated with microgreen production is warranted. The present study aimed to determine the fate and persistence of a human norovirus (HuNoV) surrogate, Tulane virus (TV), within a microgreen production system. Initially, the persistence of TV in two types of microgreen soil-free cultivation matrix (SFCM)-BioStrate® (biostrate) and peat-was determined. On day 0, water containing 7.6 log PFU of TV was applied to SFCM in growing trays, and the trays were maintained under microgreen growth conditions. TV persisted throughout the 10-day observation in biostrate and peat with overall reductions of 3.04 and 1.76 log plaque forming units (PFU) per tray, respectively. Subsequently, the transfer of TV to microgreen edible tissue was determined when planted on contaminated SFCM. Trays containing each type of SFCM were pre-inoculated with 7.6 log PFU of TV and equally divided into two areas. On day 0, sunflower (SF) or pea shoot (PS) seeds were planted on one-half of each tray, while the other half was left unplanted to serve as a control. The microgreens were harvested on day 10, and SFCM samples were collected from planted and unplanted areas of each tray. No TV were detected from the edible portion of either type of microgreen, yet TV were still present in the SFCM. TV concentrations were significantly lower in the root-containing planted area compared with the unplanted area for both biostrate (P = 0.0282) and peat (P = 0.0054). The mean differences of TV concentrations between unplanted and planted areas were 1.22 and 0.51 log PFU/g for biostrate and peat, respectively. In a subsequent investigation, TV transfer from day 7 inoculated SFCM to microgreens edible portion was not detected either. Overall, this study characterized the viral risk in a microgreen production system, which will help to understand the potential food safety risk related to HuNoV and to develop preventive measures.

Efficacy of Manufacturer Recommendations for the Control of Salmonella Typhimurium and Listeria monocytogenes in Food Ink Capsules Utilized in 3D Food Printing Systems

The adoption of 3D food printing systems has allowed for the personalization of food properties such as color, shape, and texture. This study aimed to determine if manufacturer cleaning recommendations for stainless steel food ink capsules utilized in 3D food printers adequately control foodborne pathogens of concern, as the recommendations have not been tested. A cocktail of ∼9 log₁₀ CFU/mL each of Salmonella Typhimurium and Listeria monocytogenes was inoculated onto the interior surface of the capsules. Capsules were either unsoiled or soiled with one of the following: butter, protein powder solution, powdered sugar solution, or a mixture containing all three food components. The prepared capsules underwent one of three hygienic protocols: manual washing (MW), a dishwasher speed cycle (DSC), or a dishwasher heavy cycle (DHC). The interaction effect between DSC and the soil mixture was significant (P = 0.01), with the combination achieving an estimated mean log reduction of 5.28 (95% CI: 4.61, 6.05) for L. monocytogenes and 6.69 (95% CI: 6.03, 7.41) for S. Typhimurium. The DSC was the least effective method of cleaning when compared with MW and the DHC. No significant differences were found by placing capsules on the right or left side of the dishwasher (P > 0.1). The interaction effect between wash type and capsule position was significant (P = 0.0007), with the soil mixture and DSC combination achieving an estimated mean log reduction of 3.48 (95% CI: 2.72, 4.45) for the front-most position versus 7.92 (95% CI: 6.72, 9.31) for the back-most position. Soil matrix, cleaning protocol, and capsule position all significantly impact capsule cleanability and therefore food safety risk. The DHC is recommended, and the corners should be avoided during dishwasher loading. The current study provides practical information for consumers, restaurants, industry, and regulatory industries regarding the best practices for cleaning 3D food printers.

Evaluating the Alignment and Quality of Microgreens Training Materials Available on the Internet: A Content Analysis

Interest in microgreens, young, edible seedlings of a variety of vegetables, spices, and herbs, is growing worldwide. A recent national survey of the U.S. microgreen industry reported 48% of 176 growers learned to grow microgreens by viewing websites and videos on the internet. However, it is unknown if the content related to growing microgreens is aligned with regulations and clearly presented. The aim of this research was to conduct a content analysis to determine alignment with the Food Safety and Modernization Act Produce Safety Rule (PSR)and the presentation quality of existing microgreen training materials available on the internet. Microgreen training materials were collected using two search engines - Google and YouTube. A deductive approach was used to inform the development of three coding manuals to evaluate the training materials meeting the eligibility criteria. One was used to determine the alignment of the content and was based on the PSR. The other two manuals were used to determine the presentation quality of Google and YouTube training materials according to CDC's Quality E-learning Checklist. A total of 223 training materials (86 Google and 137 YouTube), which fulfilled the inclusion criteria, were selected for the analysis. The results of the alignment with the PSR revealed that both sources minimally covered food safety principles with several areas minimally or not addressing specific information (e.g., water testing, worker training, environmental monitoring, and record keeping). In addition, some food safety information was unclear or presented conflicting information (e.g., requirement of washing microgreens, cleaning and sanitization methods, seed treatment methods, and waste management). The Google and YouTube quality scoring systems resulted in a mean quality score of 15.81 and 22 of a maximum score of 28, respectively. These findings indicate the quality and alignment with the PSR of microgreen training materials need to be improved.

Relationship between ATP Bioluminescence Measurements and Microbial Assessments in Studies Conducted in Food Establishments: A Systematic Literature Review and Meta-Analysis

ABSTRACT

Adherence to proper environmental cleaning practices is critical in food establishments. To validate cleanliness, cleaning practices should be routinely monitored, preferably by a rapid, reliable, and cost-effective method. The aim of this study was to determine whether a correlation exists between ATP bioluminescence measurements and selected microbial assessments in studies conducted in food establishments. A systematic literature review and meta-analysis was conducted using the principles of preferred reporting items for systematic reviews and meta-analyses. Twelve online databases and search engines were selected for the review. Peer-reviewed articles published in English between January 2000 and July 2020 were included in the search. From a total of 19 eligible studies, 3 that included Pearson correlation coefficients (r) between ATP bioluminescence measurements and microbial assessments were used for the meta-analysis calculations. Only the fixed-effect model produced a strong correlation because one value dominated the estimates: r = 0.9339 (0.9278, 0.9399). In contrast, both the random effects model, 0.2978 (0.24, 0.3471), and the mixed effects model, r = 0.3162 (-0.0387, 0.6711), indicated a weak relationship between ATP bioluminescence and microbial assessments, with no evidence of a strong correlation. The meta-analysis results indicated no sufficient evidence of a strong correlation between ATP bioluminescence measurements and microbial assessments when applied within food establishments. This lack of evidence for a strong correlation between the results of these two monitoring tools suggests that food establishments cannot depend on only one method. Yet, with immediate feedback and quantification of organic soiling, ATP bioluminescence could be an effective monitoring tool to use in food establishments.

HIGHLIGHTS

Transfer of Phi6 Bacteriophage Between Human Skin and Surfaces Common to Consumer-Facing Environments

AIMS

This study aimed to determine the extent of Phi6 (Φ6) transfer between skin and surfaces relevant to consumer-facing environments based on inoculum matrix, surface type, and contact time.

METHODS AND RESULTS

Φ6 transfer rates were determined from skin-to-fomite and fomite-to-skin influenced by inoculum matrix (artificial saliva and tripartite), surface type (aluminum, plastic, stainless steel, touchscreen, vinyl, and wood) and contact time (5 and 10 s). Significant differences in estimated means were observed based on surface type (both transfer directions), inoculum matrix (skin-to-fomite), and contact time (both transfer directions). During a sequential transfer experiment from fomite-to-skin, the maximum number of consecutive transfer events observed was 3.33 ± 1.19, 2.33 ± 1.20, and 1.67 ± 1.21 for plastic, touchscreen, and vinyl, respectively.

CONCLUSIONS

Contact time significantly impacted Φ6 transfer rates, which may be attributed to skin absorption dynamics. Surface type should be considered for assessing Φ6 transfer rates.

SIGNIFICANCE AND IMPACT OF THE STUDY

Although the persistence of Φ6 on fomites has been characterized, limited data is available regarding the transfer of Φ6 amongst skin and fomites. Determining Φ6 transfer rates for surfaces in consumer-facing environments based on these factors is needed to better inform future virus transmission mitigation strategies.

Temperature, Time, and Type, Oh My! Key Environmental Factors Impacting the Recovery of Salmonella Typhimurium, Listeria monocytogenes, and Tulane Virus from Surfaces

ABSTRACT

Environmental monitoring (EM) programs are designed to detect the presence of pathogens in food manufacturing environments, with the goal of preventing microbial contamination of food. Nevertheless, limited knowledge exists regarding the influence of environmental conditions on microbial recovery during EM. This study uses a commercially available polyurethane foam EM tool to determine the influence of environmental factors on the recovery of foodborne pathogens. The specific objectives of this study were to determine if environmental conditions and surface composition impact the recovery of sought-after microorganisms found in food processing environments. These data are compared across (i) microorganism type, (ii) surface type, (iii) environmental temperature and relative humidity (RH), and (iv) exposure time. Two bacteria (Listeria monocytogenes and Salmonella Typhimurium) and one human norovirus surrogate (Tulane virus) were inoculated onto three nonporous surfaces (polypropylene, stainless steel, and neoprene). Surfaces were held in an environmental chamber for 24 or 72 h at 30°C with 30% RH, 6°C with 85% RH, and 30°C with 85% RH. Data indicate that microbial recovery from environmental surfaces significantly (P ≤ 0.05) varies by microorganism type, environmental conditions, and exposure time. For instance, all microorganisms were significantly different from each other, with the greatest mean log reduction being Tulane virus and the lesser reduction being L. monocytogenes at 4.94 ± 1.75 log PFU per surface and 2.54 ± 0.91 log CFU per surface, respectively. Overall, these data can be used to improve the effectiveness of EM programs and underscores the need to better comprehend how EM test results are impacted by food manufacturing environmental conditions.

HIGHLIGHTS

Persistence of SARS-CoV-2 on Surfaces and Relevance to the Food Industry

Determining the prevalence and persistence of viruses outside the human host aids our ability to characterize exposure risk across multiple transmission pathways. Since 2020, the Coronavirus Disease 2019 pandemic has resulted in a surge of research regarding severe acute respiratory syndrome-coronavirus-type 2 (SARS-CoV-2) and its potential to spread via direct and indirect contact transmission routes. Here, the authors discuss the current state of the science concerning SARS-CoV-2 transmission via contaminated surfaces and its persistence on environmental surfaces. This review aims to provide the reader with an overview of the currently published SARS-CoV-2 persistence studies, factors impacting persistence, guidelines for performing persistence studies, limitation of current data, and future directions for assessing SARS-CoV-2 persistence on fomites.

Association of Exposure to High-risk Antibiotics in Acute Care Hospitals With Multidrug-Resistant Organism Burden in Nursing Homes

IMPORTANCE

Little is known about the contribution of hospital antibiotic prescribing to multidrug-resistant organism (MDRO) burden in nursing homes (NHs).

OBJECTIVES

To characterize antibiotic exposures across the NH patient's health care continuum (preceding health care exposure and NH stay) and to investigate whether recent antibiotic exposure is associated with MDRO colonization and room environment contamination at NH study enrollment.

DESIGN, SETTING, AND PARTICIPANTS

This is a secondary analysis of a prospective cohort study (conducted from 2013-2016) that enrolled NH patients and followed them up for as long as 6 months. The study was conducted in 6 NHs in Michigan among NH patients who were enrolled within 14 days of admission. Clinical metadata abstraction, multi-anatomical site screening, and room environment surveillance for MDROs were conducted at each study visit. Data were analyzed between May 2019 and November 2021.

EXPOSURES

Antibiotic data were abstracted from NH electronic medical records by trained research staff and characterized by class, route, indication, location of therapy initiation, risk for Clostridioides difficile infection (C diffogenic agents), and 2019 World Health Organization Access, Watch, and Reserve (AWARE) antibiotic stewardship framework categories.

MAIN OUTCOMES AND MEASURES

The primary outcomes were MDRO colonization and MDRO room environment contamination at NH study enrollment, measured using standard microbiology methods. Multivariable logistic regression was used to identify whether antibiotic exposure within 60 days was associated with MDRO burden at NH study enrollment. Additionally, antibiotic exposure data were characterized using descriptive statistics.

RESULTS

A total of 642 patients were included (mean [SD] age, 74.7 [12.2] years; 369 [57.5%] women; 402 [62.6%] White; median [IQR] NH days to enrollment, 6.0 [3.0-7.0]). Of these, 422 (65.7%) received 1191 antibiotic exposures: 368 (57.3%) received 971 hospital-associated prescriptions, and 119 (18.5%) received 198 NH-associated prescriptions. Overall, 283 patients (44.1%) received at least 1 C diffogenic agent, and 322 (50.2%) received at least 1 high-risk WHO AWARE antibiotic (watch or reserve agent). More than half of NH patients (364 [56.7%]) and room environments (437 [68.1%]) had MDRO-positive results at enrollment. In multivariable analysis, recent antibiotic exposure was positively associated with baseline MDRO colonization (odds ratio [OR], 1.70; 95% CI, 1.22-2.38) and MDRO environmental contamination (OR, 1.67; 95% CI, 1.17-2.39). Exploratory stratification by C diffogenic agent exposure increased the effect size (MDRO colonization: OR, 1.99; 95% CI, 1.33-2.96; MDRO environmental contamination: OR, 1.86; 95% CI, 1.24-2.79). Likewise, exploratory stratification by exposure to high-risk WHO AWARE antibiotics increased the effect size (MDRO colonization: OR, 2.32; 95% CI, 1.61-3.36; MDRO environmental contamination: OR, 1.86; 95% CI, 1.26-2.75).

CONCLUSIONS AND RELEVANCE

The findings of this study suggest that high-risk, hospital-based antibiotics are a potentially high-value target to reduce MDROs in postacute care NHs. This study underscores the potential utility of integrated hospital and NH stewardship programming on regional MDRO epidemiology.

Critical Factors and Emerging Opportunities in Food Waste Utilization and Treatment Technologies

Globally, approximately one-third of food produced for human consumption is lost or discarded, comprising 1. 3 billion tons annually. Factors contributing to food waste from the food manufacturer to the consumer level are numerous. Events that may result in food waste include, but are not limited to, manufacturing food by-products, improper handling within the supply chain (e.g., cold chain deviations), misunderstood food date labels, over-purchasing, and consumer-level temperature abuse. From the manufacturer to consumer, each node in the food supply requires concerted efforts to divert food waste from entering municipal landfills. Depending on the state of the food waste, it is diverted to various outlets, from food donation for consumption to composting for soil amendment. To better understand the opportunities in the United States to divert food waste from landfills, current and emerging federal policies as well as the causes of food waste generation must be understood. Unfortunately, information on both the composition of food waste in the U.S. and how it impacts critical factors in food waste treatment, especially in food waste composting, is limited. Specifically, this review aims to: (1) discuss and compare critical factors that impact the fate of food waste and (2) examine emerging opportunities to advance the processing and products of food waste.

New Approach to Food Safety Training: A Review of a Six-Step Knowledge-Sharing Model

Significant resources, including both human and financial capital, have been dedicated to developing and delivering food handler training programs to meet government and organizational mandates. Even with the plethora of food safety-oriented training programs, there is scant empirical evidence documenting effectiveness, suggesting the need to rethink the design and delivery of food safety training for food handlers. One underlying assumption of most training programs is that food handlers engage in unsafe practices because of lack of knowledge. As a result, many training curricula are designed to improve knowledge, assuming behavior will change as knowledge increases. However, food handlers often return to the work environment and try to implement the new knowledge with minimal success. One explanation for this is that the training context and the implementation context often differ, making it difficult for the food handler to transfer what they learned into practice. Understanding the connection between knowledge, the organization, and its environment is critical to knowledge implementation. The focus of this review is to describe a six-step knowledge-sharing model. Here, knowledge sharing is broadly defined as the process of creating and then using knowledge to change a practice or behavior. Our proposed knowledge-sharing model includes six steps: generation, adaptation, dissemination, reception, adoption, and implementation. We have organized this model into two dyads: (i) transfer between researcher (i.e., knowledge generators) and educator and (ii) transfer between educator and food handler (i.e., knowledge implementers). To put into practice this proposed model for developing and delivering effective food safety training for food handlers, we have provided suggested actions that can be performed within each step of the knowledge-sharing process.

Environmental contamination with SARS-CoV-2 in nursing homes

BACKGROUND

SARS-CoV-2 outbreaks in nursing homes (NHs) have been devastating and have led to the creation of coronavirus disease 2019 (COVID-19) units within NHs to care for affected patients. Frequency and persistence of SARS-CoV-2 environmental contamination in these units have not been studied.

METHODS

A prospective cohort study was conducted between October 2020 and January 2021 in four Michigan NHs. Swabs from high-touch surfaces in COVID-19-infected patient rooms were obtained at enrollment and follow-up. Demographic and clinical data were collected from clinical records. Primary outcome of interest was the probability of SARS-CoV-2 RNA detection from specific environmental surfaces in COVID-19 patient rooms. We used multivariable logistic regression to assess patient risk factors for SARS-CoV-2 contamination. Pairwise Phi coefficients were calculated to measure correlation of site-specific environmental detection upon enrollment and during follow-up.

RESULTS

One hundred and four patients with COVID-19 were enrolled (61.5% >80 years; 67.3% female; 89.4% non-Hispanic White; 51% short stay) and followed up for 241 visits. The study population had significant disabilities in activities of daily living (ADL; 81.7% dependent in four or more ADLs) and comorbidities, including dementia (55.8%), diabetes (40.4%), and heart failure (32.7%). Over the 3-month study period, 2087 swab specimens were collected (1896 COVID-19 patient rooms, 191 common areas). SARS-CoV-2 positivity was 28.4% (538/1896 swabs) on patient room surfaces and 3.7% (7/191 swabs) on common area surfaces. Nearly 90% (93/104) of patients had SARS-CoV-2 contamination in their room at least once. Environmental contamination upon enrollment correlated with contamination of the same site during follow-up. Functional independence increased the odds of proximate contamination.

CONCLUSIONS

Environmental detection of viral RNA from surfaces in the rooms of COVID-19 patients is nearly universal and persistent; more investigation is needed to determine the implications of this for infectiousness. Patients with greater independence are more likely than fully dependent patients to contaminate their immediate environment.

Reduction of Norovirus Surrogates Alone and in Association with Bacteria on Leaf Lettuce and Tomatoes During Application of Aqueous Ozone

Retail foodservice establishments (FSE) frequently utilize washes with sanitizing agents during fresh produce preparation. This study evaluated the efficacy of ozonated water on the inactivation of viruses, bacteria, and viruses in association with bacteria on produce surfaces. Boston bibb lettuce (BB) and cherry tomatoes were spot inoculated with viruses (murine norovirus (MNV) and MS2 bacteriophage), bacteria (Enterobacter cloacae and Bacillus cereus), or MNV associated with E. cloacae or B. cereus. Following inoculation, produce was held at 4 °C for 90 min (virus, virus + bacteria) or 24 h (virus, bacteria) prior to treatment. A batch wash ozone sanitation system (BWOSS) was prepared with ice (3-5 °C) and 0.5 ppm initial ozone concentration or no ozone. Produce samples were treated for 40 min with an ozonated water (0.86-0.99 ppm) or water-only wash with samples taken every 10 min. Samples were processed for microbial recovery, and plaque forming units (PFU) and colony forming units remaining on the produce were determined. Although microbial reductions of 99 to 99.99% were achieved during ozone treatments, few statistically significant differences (P > 0.1) were detected when comparing the ozonated water to water-only wash. Notably, a significant difference (P = 0.009) in log reduction of MNV + bacteria and MNV alone on BB was observed after 40 min ozonated water wash. Specifically, MNV with B. cereus achieved a 1-log greater reduction (2.60 log PFU/ml) compared to MNV alone (1.63 log PFU/ml). Overall, washing produce in ozonated water did not significantly increase microbial inactivation compared to water alone under the conditions presented here. Variables impacting ozone wash effectiveness should be considered when implementing produce wash sanitation systems within FSE.

Seasonal Patterns in Incidence and Antimicrobial Resistance of Common Bacterial Pathogens in Nursing Home Patients and Their Rooms

Background: Colonization is the main precursor to infection, which may lead to adverse clinical outcomes among older adults in nursing homes (NHs). Understanding seasonal changes in the local burden of common bacterial pathogens is key to implementing appropriate and cost-effective infection prevention measures in this resource-constrained healthcare environment. It is thus surprising that seasonal trends in patient and environmental colonization with major bacterial pathogens are presently unknown in the expanding NH setting.

Methods: We examined the seasonal incidence of four major pathogens among 640 nursing home patients and high-touch surfaces within their rooms over 2 years. In cases where a significant number of antimicrobial-resistant strains was found, incidence in antimicrobial-susceptible and antimicrobial-resistant isolates was compared, along with antibiotic use trends.

Results: We observed spring peaks in the incidence of vancomycin-resistant enterococci (1.70 peak to trough ratio for both patient and environmental isolates) and methicillin-resistant Staphylococcus aureus (1.95 peak to trough ratio for patient isolates, 1.50 for environmental isolates). We also observed summer peaks in Klebsiella pneumoniae (1.83 and 1.82 peak to trough ratio for patient and environmental isolates, respectively), and ciprofloxacin-resistant Escherichia coli. Susceptible S. aureus and E. coli did not follow seasonal patterns.

Conclusions: A meaningful seasonal pattern may be present in the NH setting for several significant pathogens, and especially antimicrobial-resistant ones. Whether such patterns are consistent across geographic areas and over longer periods of time should be a key focus of investigation, in order to better inform timing of surveillance and infection prevention efforts in this setting.

Effectiveness of a Multicomponent Intervention to Reduce Multidrug-Resistant Organisms in Nursing Homes: A Cluster Randomized Clinical Trial

IMPORTANCE

Multidrug-resistant organisms (MDROs) can cause significant morbidity and mortality. Preventing MDROs can reduce the risk of subsequent transmission and infection.

OBJECTIVE

To determine whether a multicomponent infection prevention intervention can reduce MDRO prevalence in nursing homes (NHs).

DESIGN, SETTING, AND PARTICIPANTS

This cluster randomized clinical trial of a multicomponent intervention was conducted in 6 NHs in Michigan from September 2016 to August 2018. Three NHs adopted a multicomponent intervention, while 3 control NHs continued without investigator intervention. Study visits were conducted at baseline; days 7, 14, 21, and 30; and monthly thereafter for up to 6 months or discharge. Visits included clinical data collection and MDRO surveillance culturing of multiple body sites and high-touch surfaces in patient rooms. Any patients who provided informed consent within 14 days of admission to the NH were enrolled in this study. Non-English speakers and patients receiving hospice care were ineligible. Analysis was performed from November 2018 to February 2020.

INTERVENTIONS

Intervention NHs adopted a multicomponent intervention that included enhanced barrier precautions, chlorhexidine bathing, MDRO surveillance, environmental cleaning education and feedback, hand hygiene promotion, and health care worker education and feedback. Control nursing homes continued standard care practices.

MAIN OUTCOMES AND MEASURES

The primary outcome, presence of MDROs, was measured longitudinally in the patient and room environment and was evaluated using generalized mixed effect models. The secondary outcome, time to new MDRO acquisition, was assessed using Cox proportional hazard models.

RESULTS

A total of 6 NHs were included, with 245 patients (mean [SD] age, 72.5 [13.6] years; 134 [54.7%] women) enrolled; 3 NHs with 113 patients (46.1%) were randomized to the intervention group and 3 NHs with 132 patients (53.9%) were randomized to the control group. A total of 132 patients (53.9%) were White, and 235 patients (95.9%) were receiving postacute care. Over 808 study visits, 3654 patient cultures and 5606 environmental cultures were obtained. The intervention reduced the odds of MDRO prevalence in patients' environment by 43% (aOR, 0.57; 95% CI, 0.35-0.94), but there was no statistically significant difference on the patient level before or after adjustment (aOR, 0.57; 95% CI, 0.29-1.14). There were no significant reductions in time to new acquisition for methicillin-resistant Staphylococcus aureus (hazard ratio [HR], 0.20; 95% CI, 0.04-1.09), vancomycin-resistant enterococci (HR, 0.84; 95% CI, 0.46-1.53), or resistant gram-negative bacilli (HR, 1.14; 95% CI, 0.73-1.78).

CONCLUSIONS AND RELEVANCE

This cluster randomized clinical trial found that the multicomponent intervention reduced the prevalence of MDROs in the environment of NH patients. Our findings highlight the potential for multicomponent interventions to directly and indirectly reduce MDRO prevalence in NHs.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02909946.

Factors impacting microbial release from environmental monitoring tools

The U.S. FDA Food Safety Modernization Act Preventive Controls for Human Food Rule underlines the importance of an effective environmental monitoring (EM) program. EM is used to determine harborage sites of microorganisms on processing equipment, assess effectiveness of sanitation programs, and prevent transmission of foodborne pathogens. This study characterizes commercially-available polyurethane foam (PUF) and cellulose (CELL) EM tools for their efficacy in the release of foodborne pathogens from their sponge matrices. Specifically, the objectives of this study were to 1) compare the ability of EM tools to release microorganisms into a recovery eluent, 2) characterize EM tool performance at decreasing inoculum concentrations, and 3) assess the impact of various operators during the processing of EM samples. Two bacteria (Listeria monocytogenes, Salmonella Typhimurium) and one human norovirus surrogate (Tulane virus [TV]) were compared at decreasing inoculum levels utilizing two elution techniques (mechanical stomacher, manually by operator), and across six operators. Data indicated that EM tool material composition impacted the release of microorganisms (p = 0.0001), where the PUF EM tool released TV more readily than the CELL EM tool. Conversely, the decreasing inoculum levels did not statistically differ in the release of microorganisms from the EM tool matrices. In addition, no significant difference was found between the machine stomacher and manual elution by human operator or between operators. Overall, the study provides a detailed characterization of two commercially-available EM tools, and the differences identified in this study can be used to improve the effectiveness of EM programs.

Characterization of Polyurethane Foam Environmental Monitoring Tools for the Recovery and Release of Viruses

The U.S. FDA Food Safety Modernization Act Preventive Controls for Human Food Rule emphasizes the importance of an effective environmental monitoring (EM) program. This study aims to characterize polyurethane foam (PUF) EM tools-currently used in the food industry for the recovery of bacteria from food contact surfaces-for their efficacy in the release and recovery of human enteric viruses. Two viruses (human norovirus [hNoV] and Tulane virus [TV]) were compared at varying inoculum levels, with two EM tools (PUF swab and sponge), two delayed processing times (24 h and 72 h), and one surface type (stainless steel [SS]). Specifically, the objectives were to (1) determine the ability of PUF devices to release viruses for detection and (2) assess the ability of PUF devices to recover viruses from SS surfaces. For TV release from the sponge, there was a significant difference (p = 0.0064) when compared across inoculum level (10⁵ plaque forming unit [PFU]/sponge vs. 10² PFU/sponge). Release of hNoV at a single inoculum level by PUF sponge and swab was compared resulting in a significant difference (p < 0.0001). Data on recovery of TV from SS surfaces using both the sponge and swab indicate significant differences depending on the inoculum level. Recovery of hNoV from SS surfaces differed significantly (p = 0.0030) between the sponge and swab devices. Overall, the study provides a detailed characterization of two commercially available, PUF-based EM tools, and the differences identified in this study can be used to improve the efficacy of EM tools.

The mental health impacts of climate change: Findings from a Pacific Island atoll nation

BACKGROUND

Climate change is anticipated to have profound effects on mental health, particularly among populations that are simultaneously ecologically and economically vulnerable to its impacts. Various pathways through which climate change can impact mental health have been theorised, but the impacts themselves remain understudied.

PURPOSE

In this article we applied psychological methods to examine if climate change is affecting individuals' mental health in the Small Island Developing State of Tuvalu, a Pacific Island nation regarded as exceptionally vulnerable to climate change. We determined the presence of psychological distress and associated impairment attributed to two categories of climate change-related stressors in particular: 1) local environmental impacts caused or exacerbated by climate change, and 2) hearing about global climate change and contemplating its future implications.

METHODS

The findings draw on data collected in a mixed-method study involving 100 Tuvaluan participants. Data were collected via face-to-face structured interviews that lasted 45 min on average and were subjected to descriptive, correlational, and between-group analyses.

RESULTS

The findings revealed participants' experiences of distress in relation to both types of stressor, and demonstrated that a high proportion of participants are experiencing psychological distress at levels that reportedly cause them impairment in one or more areas of daily life.

CONCLUSIONS

The findings lend weight to the claim that climate change represents a risk to mental health and obliges decision-makers to consider these risks when conceptualizing climate-related harms or tallying the costs of inaction.

Survival of Salmonella enterica subsp. enterica serovar Javiana and Listeria monocytogenes is dependent on type of soil-free microgreen cultivation matrix

AIMS

This study measured the survival of Listeria monocytogenes and Salmonella enterica subsp. enterica serovar Javiana over a 10-day period on four soil-free cultivation matrix (SFCM) types in the absence of microgreens and fertilizers.

METHODS AND RESULTS

Coco coir (CC), a Sphagnum peat/vermiculite mix, Biostrate^® and hemp mat samples were inoculated with 3 × 10⁶  CFU per ml bacteria, incubated at room temperature, and analysed on day 0, 1, 3, 6, and 10. Statistically significant differences in pathogen survival were observed across multiple time points for hemp and Biostrate compared to CC, peat and bacteria in phosphate buffered saline (PBS) (P < 0·05). S. Javiana showed greater overall survival compared to Listeria (P < 0·0002). By day 10, S. Javiana persisted at the initial inoculum concentration for hemp and Biostrate while declining by 1-2 log CFU per ml in CC, peat and PBS. Listeria also persisted at the initial concentration in hemp and Biostrate but decreased to 1 log CFU per ml in peat and below the detection limit in CC and PBS.

CONCLUSIONS

Overall, there are survival differences between bacterial pathogens in SFCM used in microgreen production systems. To our knowledge, this is the first comparison of survival among SFCM involving a S. enterica serovar and L. monocytogenes, and the first study comparing CC, Biostrate and hemp.

SIGNIFICANCE AND IMPACT OF THE STUDY

Microgreens production systems predominantly utilize soil alternatives, and it is not well-understood how pathogen transmission risk may be affected by the type of SFCM. The results of this study impact the microgreen industry as media selection may be used to reduce the risk of bacterial pathogen proliferation and transmission to the plant potentially resulting in potential foodborne illness.

Food Safety Challenges and Barriers in Southern United States Farmers Markets

Purchasing fresh and local produce at farmers markets has seen an increasing trend over the past decade. However, with this rise in popularity food safety challenges need to be recognized and addressed. Farmers market managers play a significant role in ensuring that vendors implement food safety practices at the market. Thus, this study investigated the food safety perceptions of farmers markets managers and vendors in Texas and Arkansas. A total of 123 participants were surveyed, including 38 managers and 85 vendors. The survey included a series of questions to determine gaps in vendor and manager food safety knowledge as well as the barriers and factors that prevent the implementation of relevant food safety practices. The results indicate that a lack of facilities, equipment, and resources containing food safety guidelines specific to farmers markets were the major barriers to the implementation of food safety practices. In addition, only 36.7% of participants had formal food safety training (e.g., ServSafe) and approximately 50% of the market managers provided food safety materials to their vendors. Overall, these data suggest that the development of farmers market-specific training programs to enhance food safety behaviors and practices in farmers markets would be beneficial to stakeholders.

Interplay Between Patient Colonization and Environmental Contamination With Vancomycin-Resistant Enterococci and Their Association With Patient Health Outcomes in Postacute Care

Background

The clinical utility of patient and environmental surveillance screening for vancomycin-resistant enterococci (VRE) in the postacute care setting has not been definitively clarified. We assessed the longitudinal relationship between patient colonization and room contamination, and we established their association with unfavorable health outcomes.

Methods

Four hundred sixty-three postacute care patients were followed longitudinally from enrollment to discharge for up to 6 months. Multiple body and environmental sites were sampled at regular intervals to establish correlation between environmental contamination and patient colonization and with longer than expected stay, unplanned hospitalization, and infections adjusting for sex, age, race, Charlson’s comorbidity index, and physical self-maintenance score.

Results

New VRE acquisition was more likely in patients residing in contaminated rooms (multivariable odds ratio [OR] = 3.75; 95% confidence interval [CI], 1.98–7.11) and vice versa (OR = 3.99; 95% CI, 2.16–7.51). New acquisition and new contamination were associated with increased length of stay (OR = 4.36, 95% CI = 1.86–10.2 and OR = 4.61, 95% CI = 1.92–11.0, respectively) and hospitalization (OR = 2.42, 95% CI = 1.39–4.22 and OR = 2.80, 95% CI = 1.52–5.12). New-onset infections were more common with higher VRE burdens (15% in the absence of VRE, 20% when after VRE isolation only on the patient or only in the room, and 29% after VRE isolation in both the patient and the room).

Conclusions

Room contamination with VRE is a risk factor for patient colonization, and both are associated with future adverse health outcomes in our postacute care patients. Further research is warranted to establish whether VRE screening may contribute to better understanding of risk assessment and adverse outcome prevention in postacute care.

Co-culture with Enterobacter cloacae does not Enhance Virus Resistance to Thermal and Chemical Treatments

Human noroviruses (hNoV) are the primary cause of foodborne disease in the USA. Most studies on inactivation kinetics of hNoV and its surrogates are performed in monoculture, while the microbial ecosystem effect on virus inactivation remains limited. This study investigated the persistence of hNoV surrogates, murine norovirus (MNV) and Tulane virus (TuV), along with Aichi virus (AiV) under thermal and chemical inactivation in association with Gram-negative (Enterobacter cloacae) bacteria. Thermal inactivation of viruses in co-culture with E. cloacae revealed no protective effects of bacteria. At 56 °C, AiV with and without bacteria was completely inactivated by 10 min with decimal reduction values (D-values) of 41 and 43 s, respectively. Similar results were also observed for TuV. Conversely, MNV with bacteria was completely inactivated by 10 min while MNV alone remained stable up to 30 min at 56 °C. Both MNV and TuV were slightly more stable than AiV at 63 °C with TuV detection up to 2 min without bacteria. For chemical inactivation on stainless steel surfaces, viruses alone and in association with bacteria were treated with 1000 ppm sodium hypochlorite. Virus association with bacteria had no significant effect (p > 0.05) on virus resistance to bleach inactivation compared to virus alone. Specifically, exposure to 1000 ppm bleach for 5 min resulted in an average of 3.86, 2.14, and 0.94 log₁₀ PFU/ml reductions for TuV, MNV, and AiV without bacteria, respectively. Reductions in TuV, MNV, and AiV were 3.50, 1.88, and 0.61 log10 PFU/ml when associated with E. cloacae, respectively.

Indwelling urethral versus suprapubic catheters in nursing home residents: determining the safest option for long-term use

BACKGROUND

The incidence of infectious complications has not been previously compared for two types of common urinary catheters used in the long-term care setting: indwelling urethral catheters and suprapubic catheters.

AIM

To compare catheter-associated urinary tract infection (CAUTI) rates and multidrug-resistant organism (MDRO) colonization between nursing home residents with indwelling urethral and suprapubic catheters.

METHODS

Participants included 418 nursing home residents with an indwelling device enrolled in a previously published prospective targeted infection prevention study conducted between 2010 and 2013. Resident age, gender, function, comorbidities, and information on infections, antibiotic use, and recent hospitalizations were obtained at study enrolment, day 14, and every 30 days thereafter for up to one year. Microbiological samples were obtained from several anatomic sites at each visit. Cox proportional hazard models were adjusted for facility-level clustering and other covariates.

FINDINGS

In all, 208 study participants had an indwelling urinary catheter, contributing 21,700 device-days; 173 (83%) with a urethral catheter, 35 (17%) with a suprapubic catheter. After covariate adjustment, the suprapubic group had a lower incidence of CAUTI (6.6 vs 8.8 per 1000 device-days; P = 0.05), were half as likely to be hospitalized (hazard ratio (HR) = 0.46; P < 0.01) and were 23% less likely to have had antibiotics in the past 30 days (HR = 0.77; P = 0.02). Among residents catheterized ≥90 days, the mean number of MDROs isolated in the suprapubic group was significantly higher than in the urethral group (0.57 vs 0.44; P = 0.01). Ciprofloxacin-resistant Gram-negative bacilli were frequent in both groups.

CONCLUSION

Residents with a suprapubic catheter may have fewer CAUTIs, less hospitalization and less antibiotic use, but are more likely colonized with MDROs.

Key characteristics of foods with an elevated risk for viral enteropathogen contamination

Viral enteropathogens are one of the leading causative agents of foodborne illnesses in both the United States and the European Union. While human noroviruses and hepatitis A virus cause the vast majority of outbreaks and illnesses, there are handful of human enteric viruses that contribute to sporadic outbreaks worldwide including astrovirus, sapovirus, rotavirus, enterovirus and Aichi virus. In addition, hepatitis E virus is increasingly being recognized as an emerging zoonotic threat within the food supply. This review aims to briefly describe the primary human enteric viruses of concern with respect to foodborne transmission. Next, we focus on the contamination and persistence of these viruses within three high-risk food commodities-leafy greens, soft red fruits and bivalve mollusks. As opposed to detailing the specific routes by which these foods can be contaminated with enteric viruses, we have chosen to focus on their persistence and specific interactions within the food itself. Therefore, the processes of attachment and internalization of the viruses in foods have been emphasized. Looking forward, the implications of these specific interactions of human enteric viruses with leafy greens, soft red fruits and bivalve mollusks are briefly considered within the context of future prevention and control strategies.

Microgreens-A review of food safety considerations along the farm to fork continuum

The food safety implications of microgreens, an emerging salad crop, have been studied only minimally. The farm to fork continuum of microgreens and sprouts has some overlap in terms of production, physical characteristics, and consumption. This review describes the food safety risk of microgreens as compared to sprouts, potential control points for microgreen production, what is known to date about pathogen transfer in the microgreen production environment, and where microgreens differ from sprouts and their mature vegetable counterparts. The synthesis of published research to date may help to inform Good Agricultural Practices (GAPs) and Good Handling Practices (GHPs) for the emerging microgreen industry.

Identification of Factors Affecting Fecal Pollution in Beaver Lake Reservoir

Standard methods for the evaluation of recreational water quality rely on generic bacterial indicators such as . However, does not provide enough information to determine fecal source or public health risk. The stsudy objective was to determine factors influencing the presence of and host-specific markers (HSM) from upstream to downstream in Beaver Lake Reservoir (BLR). From February 2014 to September 2015, 420 base flow and rain event samples were collected from seven sites-two sites from streams (White River [WR] and War Eagle Creek) draining into BLR and five sites from within BLR. Each sample was analyzed for and by quantitative polymerase chain reaction for HSM related to human, bovine, and poultry. The data indicate that overall levels of were significantly greater in the WR and significantly lower at the most downstream sampling location in BLR. is more likely present during spring (adjusted odds ratio [aOR] = 1.86), at the WR sampling site (aOR = 3.39), or during a rain event (aOR = 2.73). Moreover, the HSM HumM2 is more likely present (aOR = 1.99) when is present. These same factors were associated with concentrations >126 most probable number 100 mL (aOR = 2.76-12.48), except the poultry marker CL was more likely associated (aOR = 3.81) than HumM2. This study revealed that both seasonal and locational factors are important variables for fecal pollution in BLR. Moreover, these same factors may apply to fecal pollution in manmade reservoirs within similar types of watersheds across the United States, as well as internationally.

Sampling methods for recovery of human enteric viruses from environmental surfaces

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Environmental surfaces (ES) are a significant route of enteric virus transmission.

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A variety of surface sampling methods are applied for virus recovery from ES.

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There is a need for standardization of ES sampling for recovery of enteric viruses.

Acute gastroenteritis causes the second highest infectious disease burden worldwide. Human enteric viruses have been identified as leading causative agents of acute gastroenteritis as well as foodborne illnesses in the U.S. and are generally transmitted by fecal-oral contamination. There is growing evidence of transmission occurring via contaminated fomite including food contact surfaces. Additionally, human enteric viruses have been shown to remain infectious on fomites over prolonged periods of time. To better understand viral persistence, there is a need for more studies to investigate this phenomenon. Therefore, optimization of surface sampling methods is essential to aid in understanding environmental contamination to ensure proper preventative measures are being applied. In general, surface sampling studies are limited and highly variable among recovery efficiencies and research parameters used (e.g., virus type/density, surface type, elution buffers, tools). This review aims to discuss the various factors impacting surface sampling of viruses from fomites and to explore how researchers could move towards a more sensitive and standard sampling method.