Angela Fraser

Recovery and Disinfection of Two Human Norovirus Surrogates, Feline Calicivirus and Murine Norovirus, from Hard Nonporous and Soft Porous Surfaces.

Human norovirus is a leading cause of foodborne disease and can be transmitted through many routes, including environmental exposure to fomites. In this study, both the recovery and inactivation of two human norovirus surrogates, feline calicivirus (FCV) and murine norovirus (MNV), on hard nonporous surfaces (glass) and soft porous surfaces (polyester and cotton) were evaluated by both plaque assay and reverse transcription quantitative PCR method. Two disinfectants, sodium hypochlorite (8.25%) and accelerated hydrogen peroxide (AHP, at 4.25%) were evaluated for disinfection efficacy. Five coupons per surface type were used to evaluate the recovery of FCV and MNV by sonication and stomaching and the disinfection of each surface type by using 5 ml of disinfectant for a contact time of 5 min. FCV at an initial titer of ca. 7 log PFU/ml was recovered from glass, cotton, and polyester at 6.2, 5.4, and 3.8 log PFU/ml, respectively, compared with 5.5, 5.2, and 4.1 log PFU/ml, respectively, for MNV with an initial titer of ca. 6 log PFU/ml. The use of sodium hypochlorite (5,000 ppm) was able to inactivate both FCV and MNV (3.1 to 5.5 log PFU/ml) below the limit of detection on all three surface types. AHP (2,656 ppm) inactivated FCV (3.1 to 5.5 log PFU/ml) below the limit of detection for all three surface types but achieved minimal inactivation of MNV (0.17 to 1.37 log PFU/ml). Reduction of viral RNA by sodium hypochlorite corresponded to 2.72 to 4.06 log reduction for FCV and 2.07 to 3.04 log reduction for MNV on all three surface types. Reduction of viral RNA by AHP corresponded to 1.89 to 3.4 log reduction for FCV and 0.54 to 0.85 log reduction for MNV. Our results clearly indicate that both virus and surface types significantly influence recovery efficiency and disinfection efficacy. Based on the performance of our proposed testing method, an improvement in virus recovery will be needed to effectively validate virus disinfection of soft porous surfaces.

The survival and inactivation of enteric viruses on soft surfaces: A systematic review of the literature.

BACKGROUND Worldwide, enteric viruses are the main cause of acute gastroenteritis. In humans, these viruses spread via person-to-person contact, food, water, and/or the environment. Their survival and inactivation on hard surfaces have been extensively studied; however, nonlaunderable soft surfaces, such as upholstery and carpet, have received little attention. The aim of this systematic review was to determine factors that influence the survival and inactivation of enteric viruses on nonlaunderable soft surfaces. METHODS EBSCO and Web of Science were searched for experimental studies published between 1965 and 2015 using Preferred Reporting Items for Systematic Reviews and Meta-Analyses methods. Titles and abstracts were screened using 3 eligibility criteria. The quality of all study methods was also assessed. RESULTS Our search yielded 12 articles. Viruses survived between 0 hours and 140 days depending on surface and environment conditions. Virus survival was influenced by temperature, relative humidity, organic content, and deposition method. A variety of chemistries were tested across studies and were shown to have a varied effect on enteric viruses. Chlorine, glutaraldehyde, vaporous ozone, and hydrogen peroxide were the most efficacious against enteric viruses (> 3-log reduction). CONCLUSIONS Environmental factors, such as temperature and relative humidity, can influence survival of enteric viruses on nonlaunderable soft surfaces. The efficacy of liquid and vaporous chemistries are associated with surface and virus type.

The effect of hand-hygiene interventions on infectious disease-associated absenteeism in elementary schools: A systematic literature review

Background: Hand‐hygiene interventions are widely used in schools but their effect on reducing absenteeism is not well known. Methods: The aim of our literature review was to determine whether implementation of a hand‐hygiene intervention reduced infectious disease‐associated absenteeism in elementary schools. The eligible studies (N = 19), published between 1996 and 2014, were summarized and the methodologic quality of each was assessed. Results: Our review indicated evidence is available to show hand‐hygiene interventions had an effect on reducing acute gastrointestinal illness‐associated absenteeism but inadequate evidence is available to show an effect on respiratory illness‐associated absenteeism. Conclusions: The methodologic quality assessment of eligible studies revealed common design flaws, such as lack of randomization, blinding, and attrition, which must be addressed in future studies to strengthen the evidence base on the effect of hand‐hygiene interventions on school absenteeism.

DIFFERENCES IN MEDICAL AND LIFE-STYLE RISK FACTORS FOR MALNUTRITION IN LIMITED-RESOURCE OLDER ADULTS IN A RURAL U.S. STATE: A DESCRIPTIVE STUDY

ObjectivesMedical and life-style factors are associated with malnutrition in older adults. This study assessed the presence of these risk factors in limited-resource, community-dwelling older adults to inform the development of a nutrition education interventions.DesignQuantitative descriptive study.SettingA total of 24 randomly selected congregate nutrition sites (where limited-resource older adults can receive one hot meal/day, five days/week) in the rural state of South Carolina, USA.ParticipantsData were collected from 477 older adults (of the 407 who reported race, 219 were African American and 171 were White).MeasurementsExtension Educators who work for the Cooperative Extension Service (a formalized educational outreach system associated with some U.S. universities) read aloud a 27-item instrument designed to assess risk factors for malnutrition. Response frequencies were tabulated and chi-square tests were performed using SAS 9.3.ResultsMore African Americans reported having a chronic illness or condition (81.2 vs. 68.3%; p=0.003), eating alone (66.2 vs. 53.6%; p=0.012), having a refrigerator that sometimes did not keep food cold (31.8 vs. 8.4%; p<0.0001), and sometimes not having enough money to buy food (38.9 vs. 18.5%; p<0.0001) compared to White older adults.ConclusionRural older adults who attend congregate nutrition sites, especially African Americans, could be at risk for malnutrition due to health status and food preparation-related factors. Evidence-based, tailored programs are needed to minimize malnutrition among limited-resource older adults living in rural areas in the U.S..

Refrigerated Shelf Life of a Coconut Water-Oatmeal Mix and the Viability of Lactobacillus Plantarum Lp 115-400B

Non-dairy probiotic products have the advantage of being lactose-free and can be manufactured to sustain the growth of probiotics. In this study, coconut water and oatmeal were used with the probiotic, Lactobacillus plantarum Lp 115-400B (L. plantarum) as a starter culture. Two separate treatments were carried out probiotic (P) and probiotic and prebiotic (PP) added. In both treatments, oatmeal-coconut water matrix was inoculated with 7 log CFU/g of L. plantarum and fermented at 27 °C for 10 h. For the PP treatment, 1 g of inulin/100 mL of the product was added additionally. The fermented products were then refrigerated (4 °C) and the viability of L. plantarum, pH, total acidity, and apparent viscosity of the matrix were monitored at selected time intervals. The shelf life to reach was defined by maintenance of L. plantarum count of 7 log CFU/g product. Refrigerated shelf life was determined to be seven-weeks for the P treatment and five-weeks for PP treatment. A significant reduction of pH was observed at the end of the considered shelf life; conversely, the apparent viscosity of the product did not change significantly.

Effectiveness of cold-serving units using two cold-holding methods in foodservice operations.

Effectiveness of two cold-holding methods commonly used to maintain temperatures of products held on cold-serving units (CSU) was determined by time-temperature and bacterial growth patterns of three products. Products used were bulk (2.27 kg) and portioned (100 g) cottage cheese, portioned (100 g) tuna salad, and deviled eggs halves (100 ± 10 g). All products were held on a cold-serving unit using the mechanical/ice cold-holding method (mechanical cooling used in combination with 3 to 10 cm ice) for 24 h (control; laboratory setting), as well as on three separate cold-serving units using the mechanical cold-holding method (at three university residence hall field sites under actual operating conditions) for 4 h (maximum length of service). Temperatures of all bulk and portioned products held on CSUs using the mechanical/ice cold-holding method (initial temperatures of food were 4 to 8.2°C) were >7.2°C after 2 h with a 50% load factor. When the mechanical cold-holding method was used, all portioned products (initial temperatures were 8.2 to 11°C) were <7.2°C after 2 h with a 75% load factor. Temperature differences between the mechanical and mechanical/ice cold-holding methods were attributed to ice on the cold-serving unit. The ice insulated the products from the mechanically cooled basin and allowed internal temperatures of the products to increase. Statistical significance for bacterial growth patterns was reported only for products held on cold-serving units using the mechanical/ice cold-holding method: mesophilic growth in deviled eggs (p<0.05) and psychrotrophic growth in tuna salad (p<0.001). As expected, bulk cottage cheese had a significantly higher temperature over time (p<0.05) than did portioned cottage cheese for both methods of cold-holding. Based on results of this study, portioned foods on cold-serving units should be held less than 2 h when the mechanical/ice cold-holding method is used, or up to 4 h when the mechanical cold-holding method is available.

Recovery Optimization and Survival of the Human Norovirus Surrogates Feline Calicivirus and Murine Norovirus on Carpet

ABSTRACT Carpets have been implicated in prolonged and reoccurring outbreaks of human noroviruses (HuNoV), the leading cause of acute gastroenteritis worldwide. Viral recovery from environmental surfaces, such as carpet, remains undeveloped. Our aim was to determine survival of HuNoV surrogates on an understudied environmental surface, carpet. First, we measured the zeta potential and absorption capacity of wool and nylon carpet fibers, we then developed a minispin column elution (MSC) method, and lastly we characterized the survival of HuNoV surrogates, feline calicivirus (FCV) and murine norovirus (MNV), over 60 days under 30 and 70% relative humidity (RH) on two types of carpet and one glass surface. Carpet surface charge was negative between relevant pH values (i.e., pH 7 to 9). In addition, wool could absorb approximately two times more liquid than nylon. The percent recovery efficiency obtained by the MSC method ranged from 4.34 to 20.89% and from 30.71 to 54.14% for FCV and MNV on carpet fibers, respectively, after desiccation. Overall, elution buffer type did not significantly affect recovery. Infectious FCV or MNV survived between <1 and 15 or between 3 and 15 days, respectively. However, MNV survived longer under some conditions and at significantly (P < 0.05) higher titers compared to FCV. Albeit, surrogates followed similar survival trends, i.e., both survived longest on wool then nylon and glass, while 30% RH provided a more hospitable environment compared to 70% RH. Reverse transcription-quantitative PCR signals for both surrogates were detectable for the entire study, but FCV genomic copies experienced significantly higher reductions (<3.80 log10 copies) on all surfaces compared to MNV (<1.10 log10 copies). IMPORTANCE Human noroviruses (HuNoV) are the leading cause of acute gastroenteritis worldwide. Classical symptoms of illness include vomiting and diarrhea which could lead to severe dehydration and death. HuNoV are transmitted by the fecal-oral or vomitus-oral route via person-to-person contact, food, water, and/or environmental surfaces. Published laboratory-controlled studies have documented the environmental stability of HuNoV on hard surfaces, but there is limited laboratory-based evidence available about survival on soft surfaces, e.g., carpet and upholstered furniture. Several epidemiological reports have suggested soft surfaces may be HuNoV fomites illustrating the importance of conducting a survival study. The three objectives of our research were to demonstrate techniques to characterize soft surfaces, develop a viral elution method for carpet, and characterize the survival of HuNoV surrogates on carpet. These results can be used to improve microbial risk assessments, the development of much-needed soft surface disinfectant, and standardizing protocols for future soft surface studies.

Presence of human noroviruses on bathroom surfaces: a review of the literature

Abstract Enteric viruses are the most common cause of acute gastroenteritis worldwide with most cases of illness attributed to caliciviruses, such as human noroviruses (HuNoV). While environmental transmission of HuNoV is reported to be low, environmental surfaces could be a source of secondary transmission. As many vomiting/fecal episodes occur in bathrooms, bathroom surfaces could be an important vehicle for transmitting HuNoV. We systematically reviewed the literature to determine the presence of HuNoV on bathroom surfaces. Our review included 22 eligible studies conducted in commercial and institutional settings. Under outbreak conditions, 11 studies reported detection rates of 20–100 %. Six studies implicated bathroom surfaces as primary sources of HuNoV infection while three reported HuNoV present on bathroom surfaces but indicated different primary sources. Under non-outbreak conditions, five studies reported detection rates of 2–17 %. Factors associated with HuNoV presence in bathrooms included population density, setting type, employee numbers, food handler knowledge, awareness, and behaviours, and cleaning/disinfecting procedures. Our review suggests bathrooms could be vehicles that transmit HuNoV under both outbreak and non-outbreak conditions.

An observational study of frequency of provider hand contacts in child care facilities in North Carolina and South Carolina.

BACKGROUND Children enrolled in child care are 2.3-3.5 times more likely to experience acute gastrointestinal illness than children cared for in their own homes. The purpose of this study was to determine the frequency surfaces were touched by child care providers to identify surfaces that should be cleaned and sanitized. METHODS Observation data from a convenience sample of 37 child care facilities in North Carolina and South Carolina were analyzed. Trained data collectors used iPods (Apple, Cupertino, CA) to record hand touch events of 1 child care provider for 45 minutes in up to 2 classrooms in each facility. RESULTS Across the 37 facilities, 10,134 hand contacts were observed in 51 classrooms. Most (4,536) were contacts with porous surfaces, with an average of 88.9 events per classroom observation. The most frequently touched porous surface was childrens clothing. The most frequently touched nonporous surface was food contact surfaces (18.6 contacts/observation). Surfaces commonly identified as high-touch surfaces (ie, light switches, handrails, doorknobs) were touched the least. CONCLUSION General cleaning and sanitizing guidelines should include detailed procedures for cleaning and sanitizing high-touch surfaces (ie, clothes, furniture, soft toys). Guidelines are available for nonporous surfaces but not for porous surfaces (eg, clothing, carpeting). Additional research is needed to inform the development of evidence-based practices to effectively treat porous surfaces.

A Review of State Licensing Regulations to Determine Alignment with Best Practices to Prevent Human Norovirus Infections in Child-Care Centers:

Objectives. Close, frequent contact between children and care providers in child-care centers presents many opportunities to spread human noroviruses. We compared state licensing regulations for child-care centers with national guidelines written to prevent human noroviruses. Methods. We reviewed child-care licensing regulations for all 50 U.S. states and the District of Columbia in effect in June 2015 to determine if these regulations fully, partially, or did not address 14 prevention practices in four topic areas: (1) hand hygiene, (2) exclusion of ill people, (3) environmental sanitation, and (4) diapering. Results. Approximately two-thirds (8.9) of the 14 practices across all state regulations were partially or fully addressed, with few (2.6) fully addressed. Practices related to exclusion of ill people and diapering were fully addressed most often, while practices related to hand hygiene and environmental sanitation were fully addressed least often. Conclusion. Regulations based on guidelines for best practices are one way to prevent the spread of human noroviruses in child-care facilities, if the regulations are enforced. Our findings show that, in mid-2015, many state child-care regulations did not fully address these guidelines, suggesting the need to review these regulations to be sure they are based on best practices