Outbreaks where food workers have been implicated in the spread of foodborne disease. Part 11. Use of antiseptics and sanitizers in community settings and issues of hand hygiene compliance in health care and food industries

Molecular detection of vancomycin and methicillin resistance in Staphylococcus aureus isolated from food processing environments

Staphylococcus aureus is a well-known foodborne pathogen. The aim of this study was to investigate the presence of S. aureus isolated from serving utensils in food processing environments in Mymensingh city, Bangladesh and to determine their antibiogram and resistance determinants. A total of 120 environmental samples were collected from different food settings. Isolation and identification were conducted using conventional biochemical tests. Molecular identification of isolates and detection of methicillin and vancomycin resistance were done using primer-specific polymerase chain reaction (PCR) targeting Tuf, nuc, mecA, and mecC genes. Antibiotic sensitivity tests were performed, and resistance genes were also detected by amplifying bla TEM , vanA, vanB, and vanC genes. Among the 120 samples, 81 (67.5%) were positive for Staphylococcus spp. and 41 (50.62%) were positive for the nuc-gene. Among the 41 isolates, 5 (12.20%) were positive for mecA, but none were positive for the mecC gene. A total of 12.2% of the isolates were vanC-positive, of which 4 isolates (9.76%) were also positive for the mecA gene. Antibiotic sensitivity testing revealed that all S. aureus isolates (100%) from hotel samples were sensitive to ciprofloxacin and chloramphenicol, 90.32% were sensitive to doxycycline, and 80.65% were sensitive to streptomycin. Conversely, all isolates (100%) were resistant to ampicillin, and 29.03% were resistant to vancomycin. All S. aureus isolates obtained from non-hotel samples were susceptible to chloramphenicol, ceftriaxone, ciprofloxacin, doxycycline, meropenem, and vancomycin; however, 40% of isolates were resistant to novobiocin. Among the hotel isolates, 29 (93.55%) of the ampicillin-resistant isolates harbored the blaTEM gene while 5 (55.55%) of the vancomycin-resistant isolates harbored the vanC gene. Four of the five vanC positive isolates were also positive for the mecA gene. The presence of methicillin-resistant S. aureus (MRSA) which is also vancomycin-resistant in food processing environments is a threat to public health. This is the first report on the molecular detection of methicillin and vancomycin-resistant S. aureus isolated from food processing environments in Bangladesh.

Efficacy of Removing Bacteria and Organic Dirt from Hands-A Study Based on Bioluminescence Measurements for Evaluation of Hand Hygiene When Cooking

The objective of this study was to evaluate the efficacy of dirt removal (bacteria and organic matter) of several hand-cleaning procedures. The results from the hand hygiene experiment indicated that washing hands with warm water and soap for 20 s is the most effective method investigated when hands are either dirty or greasy. Even if not proper washing, rinsing under running water for 5 s is a cleaning procedure that may significantly reduce the probability of cross-contamination, as it removes 90% of the hands’ dirt. Although less effective than water and soap, the usage of antibacterial wipes was significantly more effective than wet wipes, indicating that they are a better choice when water and soap are not available. The results of this study enable us to inform consumers about the effectiveness of hand-cleaning procedures applied in their homes when cooking. Moreover, it can make consumers understand why, during the COVID-19 pandemic, authorities recommended washing hands as a preventive measure of infection and using an anti-bacterial hand gel or wiping hands with an antimicrobial wipe if water and soap are not available.

Exploratory study to determine if risk factors for occupational skin disease vary by type of food processing operation

BACKGROUND

Occupational skin disease (OSD) is a common health issue in the food processing sector. However, risk factors for OSD are suspected to differ according to the nature of the operation.

OBJECTIVE

To ascertain if the risk factors for OSD vary depending on the type of food processing operation, namely meat processing vs. a commercial bakery.

METHODS

Participants were asked to answer questions regarding workplace exposures and the current skin condition of their hands. Bivariate analyses were conducted to identify differences between the two participating operations.

RESULTS

The meat processing workers were more likely to have wet work exposure, used hand sanitizer more often and changed their gloves more frequently. These findings from meat processing represented a statistically significant difference compared to the commercial bakery workers. Also, workers from meat processing reported more severe skin symptoms.

CONCLUSIONS

Risk factors for OSD apparently differ between types of food processing operations. Differences in the nature of skin symptoms were also found between the two participating operations. It is therefore suggested that future studies examining OSD within the food processing sector should evaluate this health effect based on the nature of operations rather than the sector as a whole.

Carriage, Risk Factors, and Antimicrobial Resistance Patterns of Salmonella Isolates from Raw Beef in Jimma, Southwestern Ethiopia

Purpose

Consumption of raw beef infected with multidrug-resistant Salmonella is pertinent to the world public health risk of antimicrobial resistance. Henceforth, this study aimed to investigate the carriage, antimicrobial resistance (AR) patterns, and the revealing risk factors of Salmonella-contaminating beef in abattoirs and butcher shops in Jimma town.

Methods

A cross-sectional study was conducted to investigate the carriage and AR patterns and to reveal the risk factors of beef contaminated by Salmonella spp. Three hundred and forty-eight swab samples were collected from abattoirs (n=210) and butcher shops (n=138) and the conventional cultural methods were employed for identification of Salmonella. Isolates were subjected to 12 antimicrobials using the Kirby-Bauer disk diffusion method for AR patterns.

Results

The occurrence of Salmonella isolates from the abattoir samples was 11.4%, whereas about 6.52% of isolates were recovered from butcher shops. Educational status (abattoir: odds ratio (OR)=8.40, confidence interval (CI)=1.186-59.493; butcher shops: OR=9.17, CI=1.15-73.239), job related training (abattoir: OR=5.50, CI=1.065-28.416), contamination risk perception (abattoir: OR=5.31, CI=1.256-22.489), neatness of knives (abattoir: OR=7.6, CI=0.892-65.376), source of contamination (abattoir: OR=8.44, CI=1.682-42.39), wearing of protective cloth (butcher shops: OR=8.44, CI=1.682-42.39), manner of hand washing (butcher shops: OR=7.25, CI=1.210-43.442), and money handling (butcher shops: OR= 9.69, CI=1.578-59.474) were among the potential risk factors significantly associated with Salmonella carcass contamination in the abattoir and butcher shops. Of the 33 Salmonella isolates, 14 (58.3%) and six (66.7%) of the abattoir and butcher shops isolates, correspondingly, were resistant to two or more antibiotics.

Conclusion

The finding of this investigation exhibited extensive multidrug-resistant Salmonella isolates in the study setting. Hence, establishing standard meat safety requirements and provision of training for meat handlers and prudent use of antimicrobials are recommended.

Scientific Evidence Supports the Use of Alcohol-Based Hand Sanitizers as an Effective Alternative to Hand Washing in Retail Food and Food Service Settings When Heavy Soiling Is Not Present on Hands

ABSTRACT

Suboptimal food worker health and hygiene has been a common contributing factor in foodborne disease outbreaks for many years. Despite clear U.S. Food and Drug Administration (FDA) Model Food Code recommendations for hand washing and glove use, food worker compliance with hand washing recommendations has remained poor for >20 years. Food workers' compliance with recommended hand washing guidelines is adversely impacted by a number of barriers, including complaints of time pressure, inadequate number and/or location of hand washing sinks and hand washing supplies, lack of food knowledge and training regarding hand washing, the belief that wearing gloves obviates the need for hand washing, insufficient management commitment, and adverse skin effects caused by frequent hand washing. Although many of the issues related to poor hand washing practices in food service facilities are the same as those in health care settings, a new approach to health care hand hygiene was deemed necessary >15 years ago due to persistently low compliance rates among health care personnel. Evidence-based hand hygiene guidelines for health care settings were published by both the Centers for Disease Control and Prevention in 2002 and by the World Health Organization in 2009. Despite similar low hand washing compliance rates among retail food establishment workers, no changes in the Food Code guidelines for hand washing have been made since 2001. In direct contrast to health care settings, where frequent use of alcohol-based hand sanitizers (ABHSs) in lieu of hand washing has improved hand hygiene compliance rates and reduced infections, the Food Code continues to permit the use of ABHSs only after hands have been washed with soap and water. This article provides clear evidence to support modifying the FDA Model Food Code to allow the use of ABHSs as an acceptable alternative to hand washing in situations where heavy soiling is not present. Emphasis on the importance of hand washing when hands are heavily soiled and appropriate use of gloves is still indicated.

HIGHLIGHTS

Assessment of food safety knowledge, attitudes and practices of fish farmers and restaurants food handlers in Bangladesh

The study was conducted to assess the present status of knowledge, attitudes and practices (KAP) concerning the food safety and hygiene issues among fish farmers and food handlers in Noakhali, Bangladesh. Data were collected from 100 respondents (50 fish farmers and 50 food handlers) through face to face interviews. All the respondents agreed that training on hygiene practices was necessary and they were interested to attend training in their spare time. Food handlers (88%) agreed that raw foods must be kept separate from prepared foods and 68% of them believed that improper preservation of foods is harmful to health. About 52% of farmers used a face mask when spreading insecticides, fertilizers, and chemicals. Food handlers were wearing protective clothing (32%) and masks (12%) when touching and distributing unwrapped foods, however no handlers used a cap. A significant strong correlation coefficient (rs) was found between knowledge with attitudes, knowledge with practices and attitudes with practices of 0.73-0.99 among the three domains for fish farmers and food handlers. The correlation among the three levels was satisfactory, however, some food safety concepts and practices regarding hygiene were still insufficient. Therefore, an effective and appropriate training program on food safety and hygiene should be launched in a holistic approach for all fish farmers and food handlers to increase awareness and ensure safe food for consumers with a view to reducing the possibility of disease outbreak.

Wearable Technology Effects on Training Outcomes of Restaurant Food Handlers

Food safety training does not always result in behavior change, perhaps because of flaws inherent in traditional training designs. New technologies such as augmented reality headsets or head-mounted action cameras could transform the way food safety training is conducted in the food industry. Training conducted with wearable technology presents visual content in the first-person or actor's perspective, as opposed to the traditional third-person or observer perspective. This visual hands-on first-person perspective may provide an effective way of conveying information and encouraging behavior execution because it uses the mirror neuron system. There is little published literature about the impact of perspective on food safety training outcomes, such as motivation. The present study included a repeated-measures design to determine how first- and third-person camera angles affected hand washing training reactions among 108 currently employed restaurant food handlers. Participants were assessed on their posttraining compliance intentions, compliance self-efficacy, perceived utility of the training, overall satisfaction with the training, and video perspective preference. A significant proportion of food handlers (64%) preferred the first-person video perspective ( z = 5.00, P < 0.001), and a significant correlation was found between compliance intentions and compliance self-efficacy ( r(108) = 0.361, P < 0.001) for the first-person video. No significant differences in video preference were found for demographic variables, including age (χ² (2, n = 104) = 1.69, P = 0.430), which suggests that the first-person training format appeals to a diverse workforce. These findings support the application of wearable technology to enhance hand washing training outcomes across a wide range of demographic groups. This research lays the framework for future studies to assess the impact of instructional design on compliance concerning hand washing and other food handling behaviors.

Deposition of Bacteria and Bacterial Spores by Bathroom Hot-Air Hand Dryers

Hot-air hand dryers in multiple men's and women's bathrooms in three basic science research areas in an academic health center were screened for their deposition on plates of (i) total bacteria, some of which were identified, and (ii) a kanamycin-resistant Bacillus subtilis strain, PS533, spores of which are produced in large amounts in one basic science research laboratory. Plates exposed to hand dryer air for 30 s averaged 18 to 60 colonies/plate; but interior hand dryer nozzle surfaces had minimal bacterial levels, plates exposed to bathroom air for 2 min with hand dryers off averaged ≤1 colony, and plates exposed to bathroom air moved by a small fan for 20 min had averages of 15 and 12 colonies/plate in two buildings tested. Retrofitting hand dryers with HEPA filters reduced bacterial deposition by hand dryers ∼4-fold, and potential human pathogens were recovered from plates exposed to hand dryer air whether or not a HEPA filter was present and from bathroom air moved by a small fan. Spore-forming colonies, identified as B. subtilis PS533, averaged ∼2.5 to 5% of bacteria deposited by hand dryers throughout the basic research areas examined regardless of distance from the spore-forming laboratory, and these were almost certainly deposited as spores. Comparable results were obtained when bathroom air was sampled for spores. These results indicate that many kinds of bacteria, including potential pathogens and spores, can be deposited on hands exposed to bathroom hand dryers and that spores could be dispersed throughout buildings and deposited on hands by hand dryers.IMPORTANCE While there is evidence that bathroom hand dryers can disperse bacteria from hands or deposit bacteria on surfaces, including recently washed hands, there is less information on (i) the organisms dispersed by hand dryers, (ii) whether hand dryers provide a reservoir of bacteria or simply blow large amounts of bacterially contaminated air, and (iii) whether bacterial spores are deposited on surfaces by hand dryers. Consequently, this study has implications for the control of opportunistic bacterial pathogens and spores in public environments including health care settings. Within a large building, potentially pathogenic bacteria, including bacterial spores, may travel between rooms, and subsequent bacterial/spore deposition by hand dryers is a possible mechanism for spread of infectious bacteria, including spores of potential pathogens if present.

Assessing user acceptance towards automated and conventional sink use for hand decontamination using the technology acceptance model

Hand hygiene (HH) prevents harmful contaminants spreading in settings including domestic, health care and food handling. Strategies to improve HH range from behavioural techniques through to automated sinks that ensure hand surface cleaning. This study aimed to assess user experience and acceptance towards a new automated sink, compared to a normal sink. An adapted version of the technology acceptance model (TAM) assessed each mode of handwashing. A within-subjects design enabled N = 46 participants to evaluate both sinks. Perceived Ease of Use and Satisfaction of Use were significantly lower for the automated sink, compared to the conventional sink (p < 0.005). Across the remaining TAM factors, there was no significant difference. Participants suggested design features including jet strength, water temperature and device affordance may improve HH technology. We provide recommendations for future HH technology development to contribute a positive user experience, relevant to technology developers, ergonomists and those involved in HH across all sectors. Practitioner Summary: The need to facilitate timely, effective hand hygiene to prevent illness has led to a rise in automated handwashing systems across different contexts. User acceptance is a key factor in system uptake. This paper applies the technology acceptance model as a means to explore and optimise the design of such systems.

The environment in which behaviours are learned: a pilot assessment of high school teaching kitchens as food safety learning environments in Ontario

Youth represent a unique audience for consumer food safety education and incorporating such education into existing curricula could facilitate delivery. However, successful delivery may depend, in part, on the facilities in which said training occurs. Since little is known about school teaching kitchen set-ups as related to food safety education, we conducted a pilot assessment of the physical learning environment of four Ontario high school teaching kitchen classrooms. We visited each classroom three times and assessed its characteristics using a modified version of the provincial food premises inspection report. Kitchen layout varied by school, and it was the built classroom characteristic with the greatest potential impact. Several characteristics unique to school teaching kitchens were noted, including whether the classroom teaching area and food preparation area were separated. Despite the variation between classrooms, all had physical characteristics sufficient to meet the minimum requirements for food service premises in Ontario. Nevertheless, this pilot assessment highlights nuanced factors unique to high school teaching kitchen classrooms that may impact the delivery of food safety education and the development of safe food handing behaviours. Findings can support conversations between public health, food safety authorities, and school stakeholders to enhance food safety learning environments in schools.

The risk of carriage of Salmonella spp. and Listeria monocytogenes in food animals in dynamic populations

Salmonella spp. and Listeria monocytogenes are foodborne pathogens of global importance. We assessed their risks and associated factors in a highly dynamic population of animals. Animal and environmental samples were collected from dairy cattle, sheep, camel and chickens at either the farms or the abattoirs. The pathogens were detected using a combination of bacterial enrichment culture and real‐time polymerase chain reaction (PCR). Data on putative risk factors were collect and analysed for their significance of association with these pathogens.

Salmonella spp. were detected at higher proportions in sheep faeces and sheep carcasses in comparison to cattle faeces (odds ratio = 2.4 and 2.2, respectively). This pathogen was less common in milk or carcasses samples from cattle or chickens. Sheep and camel carcass samples were highly contaminated with Salmonella spp. Faecal samples from cattle had the most diverse serovars of Salmonella enterica including S. Newport, S. Haifa, S. Kedougou, S. Kentucky, S. Mbandaka and S. Goettingen. Exotic serovars in sheep included S. Eastbourne, S. Chester and S. Kottnus. Serovars that were shed in camel faeces included S. Newport, S. Bovismorbificans and S. Infantis. In all sampled populations, detection of Salmonella spp. was more likely during warmer months than cold months. Listeria monocytogenes was not common in the targeted populations and was detected at a rate of 2.4%, mainly from sheep carcasses. The study highlights the role of food animals as reservoirs of pathogens across boundaries since all feed are imported in that population from different parts of the world.

Consumer Poultry Handling Behavior in the Grocery Store and In-Home Storage

Considerable work on consumers' food safety habits has highlighted issues associated with home food preparation. However, consumer handling of foods, such as poultry, during shopping and storage has not been noted. The objective of this study was to determine consumer behaviors during purchasing and initial storage of raw poultry to determine potential cross-contamination issues. A shop-along observational study was conducted to determine actual shopping, transportation, and storage behavior of consumers who purchase raw poultry products. Neither hand sanitizer nor wipes were observed in 71% of grocery store meat sections of stores visited. Plastic bags could be found in the meat section 85% of the time, but only 25% of shoppers used the bag for their raw poultry purchases. During checkout, the poultry was bagged separately from other products 71% of the time. A majority of shoppers stored raw poultry in the original package without an additional container or overwrap. Overall, there needs to be an increase in food safety education on the handling of poultry during purchasing, transportation, and storage.

Risk of Escherichia coli O157:H7, Non-O157 Shiga Toxin-Producing Escherichia coli, and Campylobacter spp. in Food Animals and Their Products in Qatar

Escherichia coli O157:H7, non-O157 E. coli, and Campylobacter spp. are among the top-ranked pathogens that threaten the safety of food supply systems around the world. The associated risks and predisposing factors were investigated in a dynamic animal population using a repeat-cross-sectional study design. Animal and environmental samples were collected from dairy and camel farms, chicken processing plants, and abattoirs and analyzed for the presence of these pathogens using a combination of bacterial enrichment and real-time PCR tests without culture confirmation. Data on putative risk factors were also collected and analyzed. E. coli O157:H7 was detected by PCR at higher levels in sheep and camel feces than in cattle feces (odds ratios [OR], 6.8 and 21.1, respectively). Although the genes indicating E. coli O157:H7 were detected at a relatively higher rate (4.3%) in fecal samples from dairy cattle, they were less common in milk and udder swabs from the same animals (1 and 2%, respectively). Among the food adulterants, E. coli O103 was more common in cattle fecal samples, whereas O26 was more common in sheep feces and O45 in camel feces compared with cattle (OR, 2.6 and 3.1, respectively). The occurrence of E. coli in the targeted populations differed by the type of sample and season of the year. Campylobacter jejuni and Campylobacter coli were more common in sheep and camel feces than in cattle feces. Most of the survey and surveillance of E. coli focused on serogroup O157 as a potential foodborne hazard; however, based on the PCR results, non-O157 Shiga toxin-producing E. coli serotypes appeared to be more common, and efforts should be made to include them in food safety programs.

A quantitative exposure model simulating human norovirus transmission during preparation of deli sandwiches

Human noroviruses (HuNoVs) are a major cause of food borne gastroenteritis worldwide. They are often transmitted via infected and shedding food handlers manipulating foods such as deli sandwiches. The presented study aimed to simulate HuNoV transmission during the preparation of deli sandwiches in a sandwich bar. A quantitative exposure model was developed by combining the GoldSim® and @Risk® software packages. Input data were collected from scientific literature and from a two week observational study performed at two sandwich bars. The model included three food handlers working during a three hour shift on a shared working surface where deli sandwiches are prepared. The model consisted of three components. The first component simulated the preparation of the deli sandwiches and contained the HuNoV reservoirs, locations within the model allowing the accumulation of NoV and the working of intervention measures. The second component covered the contamination sources being (1) the initial HuNoV contaminated lettuce used on the sandwiches and (2) HuNoV originating from a shedding food handler. The third component included four possible intervention measures to reduce HuNoV transmission: hand and surface disinfection during preparation of the sandwiches, hand gloving and hand washing after a restroom visit. A single HuNoV shedding food handler could cause mean levels of 43±18, 81±37 and 18±7 HuNoV particles present on the deli sandwiches, hands and working surfaces, respectively. Introduction of contaminated lettuce as the only source of HuNoV resulted in the presence of 6.4±0.8 and 4.3±0.4 HuNoV on the food and hand reservoirs. The inclusion of hand and surface disinfection and hand gloving as a single intervention measure was not effective in the model as only marginal reductions of HuNoV levels were noticeable in the different reservoirs. High compliance of hand washing after a restroom visit did reduce HuNoV presence substantially on all reservoirs. The model showed that good handling practices such as washing hands after a restroom visit, hand gloving, hand disinfection and surface disinfection in deli sandwich bars were an effective way to prevent HuNoV contamination of the prepared foods, but it also demonstrated that further research is needed to ensure a better assessment of the risk of HuNoV transmission during preparation of foods.

Preventing and controlling foodborne disease in commercial and institutional food service settings: a systematic review of published intervention studies

This study reviews the current literature on behavioral and environmental food safety interventions conducted in commercial and institutional food service settings. A systematic search of the published literature yielded 268 candidate articles, from which a set of 23 articles reporting intervention outcomes was retained for evaluation. A categorization of measured outcomes is reported; studies addressed multiple outcomes ranging from knowledge, attitudes, and behavior of personal hygiene and food safety to management practices and disease rates and outbreaks. This study also investigates the quality of reported research methods used to evaluate the effectiveness of the interventions, using a nine-point quality index adapted by the authors. The observed scores suggest that there are opportunities to improve the design and reporting of research in the field of foodborne disease prevention as it applies to food safety interventions that target the food service industry. The aim is to aid researchers in this area to design higher quality studies and to produce clearer and more useful reports of their research. In turn, this can help to create a more complete evidence base that can be used to continually improve interventions in this domain.

Severe infections caused by Salmonella Enteritidis PT8/7 linked to a private barbecue

A cohort study on a barbecue-associated Salmonella outbreak was conducted to describe the burden of disease and to identify the outbreak vehicle. Dose-response relationships were tested with Fisher's exact and Wilcoxon rank sum tests (alpha = 0·05). S. Enteritidis isolates were cultured and phage-typed. Information was available for 11 out of 14 individuals attending the barbecue; all were healthy young adults (median age 27 years). The attack rate was 100%. Three cases were hospitalized and two developed acute pancreatitis. The exposure common to all cases was a vegetable pasta salad that had been stored unrefrigerated for 23 h. Consuming higher doses was associated with longer median symptom duration (7 days vs. 4 days, P = 0·11). S. Enteritidis was found in the stools of nine barbecue guests. Phage type 8/7 was identified in the stools of the salad preparer and one barbecue guest. This outbreak shows that S. Enteritidis can cause serious infection in young healthy individuals without well-known risk factors.

The hygienic efficacy of different hand-drying methods: a review of the evidence

The transmission of bacteria is more likely to occur from wet skin than from dry skin; therefore, the proper drying of hands after washing should be an integral part of the hand hygiene process in health care. This article systematically reviews the research on the hygienic efficacy of different hand-drying methods. A literature search was conducted in April 2011 using the electronic databases PubMed, Scopus, and Web of Science. Search terms used were hand dryer and hand drying. The search was limited to articles published in English from January 1970 through March 2011. Twelve studies were included in the review. Hand-drying effectiveness includes the speed of drying, degree of dryness, effective removal of bacteria, and prevention of cross-contamination. This review found little agreement regarding the relative effectiveness of electric air dryers. However, most studies suggest that paper towels can dry hands efficiently, remove bacteria effectively, and cause less contamination of the washroom environment. From a hygiene viewpoint, paper towels are superior to electric air dryers. Paper towels should be recommended in locations where hygiene is paramount, such as hospitals and clinics.