Restaurants and foodservice establishments are recognized as important sites for the transmission of foodborne illnesses [7], [8]. Although results from these studies differ from those obtained for MNV-1, in this present study, MNV-1 was chosen because it is more resistant to sanitization when compared with FCV. The viral titers were expressed as log PFU per tableware (surface). The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health. Further studies are needed to develop more effective ware-washing protocols for the removal of viruses from food contact surfaces/tableware items. Fig. Some disinfectants appropriate for lab use include: household bleach (5-10% solution), quaternary ammonium compounds, and … xref For more information about PLOS Subject Areas, click No, Is the Subject Area "Hypochlorites" applicable to this article? The poor virucidal activity of QAC against MNV-1 in our study could be attributed to its formulation and the types of microorganisms it is intended to kill. Whitehead and McCue, (2010) [27], and Nowak et al. The statistical analysis confirmed that the viral counts on the contaminated tableware items before and after the air-drying period were not significantly different (p>0.0001). For the control treatment, the mean reductions of MNV-1 on the plates, forks and glasses were 2.8, 1.1 and 1 log, respectively. The 200 ppm chlorine concentration that was used in the study represents the maximum concentration allowed by the FDA for sanitization of food contact surfaces [34]. Besides chlorine, another well-known category of disinfectants is known as quaternary ammonium compounds. Department of Food Science and Technology, The Ohio State University, Columbus, Ohio, United States of America. 0000002246 00000 n Briefly, the MNV-1 stock (108 PFU/ml) was seeded on the surface of each table ware and was air dried for 1 h. The virus was recovered by swab-rinse method as described in Materials and Methods, and the titer was determined by plaque assay. Discover a faster, simpler path to publishing in a high-quality journal. Confluent RAW 264.7 cells were infected with the MNV-1 at a multiplicity of infection (MOI) of 0.2. This could be attributed to the water pressure in the automatic dishwasher as well as the higher temperature used during the washing cycle. PLOS ONE promises fair, rigorous peer review, In general, MNV-1 showed to be more sensitive to the chlorine sanitizer than to the QAC and control treatments when it was in suspension (virus stock) and in the milk. Tap water was used as a control sanitizer. quaternary ammonium compounds against un-enveloped viruses and the relatively high cost of this disinfectant at ... sodium hypochlorite. The effects were studied on L. monocytogenes in vitro and on stainless steel chips inoculated with the organism. Dispatch is not recommended for use on aluminum surfaces. This suggests that MNV-1 is quite resistant to air-drying and that it could remain infectious on food contact surfaces for an extended period of time. No, Is the Subject Area "Sanitization" applicable to this article? The tableware items were washed with 100 ppm of the Monsoon detergent at 43°C for 30 s, soaked in tap water during the rinsing at 24°C for 10 s, and sanitized by soaking them in one of the sanitizing treatments at 24°C for 30 s. The test was repeated for each sanitizer and tableware item. After 1 h incubation, DMEM supplemented with 2% FBS was added to the flask and incubated at 37°C and 5% CO2 for 48 h. When extensive cytopathic effect (CPE) was observed, the virus was harvested by freeze-thawing three times at these temperatures −80°C and 37°C, respectively, to lyse the cells and release virus particles. As a result, these organisms were used as comparisons with that of murine norovirus under similar conditions. 0000005705 00000 n 0000004245 00000 n There are some possible explanations regarding the ineffectiveness of the ware-washing procedures to achieve higher reductions of the virus from the contaminated surfaces. 2 shows the effect of this air-drying on the initial MNV-1titers. A cylindrical device covered with a soft sponge was used to wash the drinking glasses (Fig. Fig. To properly identify any significant differences at low levels, the p value was set at <0.0001. This entire cycle was repeated but with the chlorine sanitizer instead. To determine the effectiveness of the sanitizers for inactivation of MNV-1 in solutions, MNV-1 stock (108 PFU/ml) was directly inoculated into DMEM or milk, followed by addition of different sanitizers including chlorine and QAC at final concentration of 200 ppm for each sanitizer, respectively. Transmission of the vast majority of foodborne norovirus infections is considered to be through the oral–fecal route, either by direct person-to-person spread or indirectly through contaminated food or water [4], [5]. This study evaluated the occurrence of practices and behaviors commonly identified by the Centers for Disease Control and Prevention (CDC) as contributing factors to foodborne illness outbreaks [9]. The literature also reports on studies using Feline Calicivirus (FCV) as a surrogate for human norovirus [15]. here. The MNV-1 reductions achieved after exposure to the sanitizing solutions when the virus was in the milk were 1.6, 2.7 and 1.3 logs (control, chlorine and QAC, respectively). Once the sanitization step was completed and the tableware items air dried for 1 h, 4 samples of each item were collected. (sodium hypochlorite), quaternary ammonium compounds (benzalkonium chlorides), and glutaraldehyde will help prevent people from getting asthma. 0000013861 00000 n Prior to the ware-washing, 4 samples of each tableware item were collected after the air drying period. The infected plates were incubated for 1 h at 37°C and 5% CO2, with agitation every 15 min. For more information about PLOS Subject Areas, click The results showed that the recovery rates from fork and drinking glass were approximately 99.5% and 99.3%, respectively. The efficacy of a solution is dependent on its pH. Sodium Hypochlorite (Chlorine Bleach) Hypochlorous acid is one of the most effective and natural disinfectant in the chlorine family available in dilute solution. It is responsible for at least 50% of all gastroenteritis outbreaks worldwide [1]. Since norovirus is highly contagious and its infectious dose is relatively low (10–100 particles), only a few infectious virus particles can cause human infection [1], [3]. For the ware washing with the QAC sanitization, the range was 1.6 to 3.2 log per tableware item. Multifactor analysis of variance (ANOVA) was used to determine the significance between the mean values. 1090 0 obj <> endobj The resulting water-detergent solution had a concentration of 3,000 ppm (v/v). Methods: Accelerated hydrogen peroxide (AHP), quaternary ammonium compounds (Quat), and sodium hypochlorite were tested at label and reduced contact times and concentrations against four MDR P. aeruginosa strains and four MRSA strains. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Results Overall, sodium hypochlorite and hydrogen peroxide disinfectants had significantly higher bactericidal efficacies than quaternary ammonium chloride disinfectants. We also determined the recovery rate for the swab-rinse method used in our study. 0000020937 00000 n WHAT IS ASTHMA? noroviruses and their surrogates) are fairly resistant to chemical agents, including QACs and chlorine-based sanitizers [25], [26]. https://doi.org/10.1371/journal.pone.0050273.g002. We also found that all tested disinfectants except for quaternary ammonium chloride disinfectants met and exceeded the EPA standard for bactericidal efficacy against biofilms. Consult manufacturer directions to determine the efficacy of the disinfectant against the biohazards in your lab and be sure to allow for sufficient contact time. 0000009810 00000 n Dairy products are known for being difficult to remove from various surfaces, especially when dried [13]. 0000021411 00000 n The initial titer of MNV-1 stock was 108 plaque forming unit (PFU)/ml. A total of 3 g of this cream cheese was then applied to the entire food contact surface of each ceramic plate. PLoS ONE 7(12): Yes Murine norovirus (MNV-1) was provided by Dr. Herbert Virgin IV from Washington University School of Medicine. The ineffectiveness of the traditional sanitizers and the ware-washing protocols to significantly remove and/or inactivate MNV-1 from contaminated surfaces is in agreement with published reports which suggested that the current food hygiene guidelines, most of which have been optimized for the prevention of bacterial infections, may not be fully effective against viruses [17], [24]. At the end of this study this objective was met. Bleach- Sodium Hypochlorite 5.25% (bleach concentrate) Phenols Quaternary Ammonium Compounds Accelerated Hydrogen Peroxide (hydrogen peroxide /anionic surfactants) Botanicals Example- Benefect – Thymol Silver Dihydrogen Citrate Example - PureGreen 24 Product Description •EPA registered chlorine bleach at a 5.25% dilution. E. coli K12 (ATCC 29181) and L. innocua (ATCC 33090) were stored in a −80°C freezer in 30% (v/v) sterile glycerol (Fisher Scientific, Fair Lawn, NJ) and revived when required for the experimental procedure. Yes These compounds are able to … 2 also shows the effect of the air-drying on the initial counts of E. coli K-12 and L. innocua cells. Sodium hypochlorite is very effective against all types of micro-organism (including spores). This is supported by a previous study conducted by Kuda et al., (2008) and Truby and Bennett (1996), where food sediments, such as milk, meat gravies, fats and certain carbohydrates are capable of adversely affected the bactericidal effect of QAC [29], [30]. %PDF-1.4 %���� The effects of three representative disinfectants, chlorine (sodium hypochlorite), iodine (potassium tetraglicine triiodide), and quaternary ammonium compound (didecyldimethylammonium chloride), on several exotic disease viruses were examined. The data showed that after washing and sanitizing with the QAC sanitizer, MNV-1 was reduced on the ceramic plates by 2.7 log and the mean reduction for both the forks and glasses were 1.6 and 1.4 log, respectively. Prior to each experiment, the machine was cleaned with hot water (49°C) and filled with fresh water. (Use only EPA This selectivity of QAC has been attributed to its ionic binding capabilities and hydrophobic interactions with microbial membrane surfaces. 0000009142 00000 n We also found that all tested disinfectants except for quaternary ammonium chloride disinfectants met and exceeded the EPA standard for bactericidal efficacy against biofilms. This causes rearrangement of the membranes and subsequently leakage of the intracellular constituents [28]. 3 and 4 reveal that even though sanitizers appear to slightly enhance the reduction of MNV-1 from contaminated tableware, there was still a considerable amount of the virus on the contaminated surfaces. 4. The preparation and infectious titer assays for MNV-1 were performed using the murine macrophage cell line RAW 264.7 (ATCC, Manassas, VA), as described by Wobus et al., (2006) [12], with minor modifications. No, Is the Subject Area "Food" applicable to this article? In this study, the organic matter would be the food soil deposited onto the table ware items. 0000021170 00000 n The food matrices used in our study were cream cheese and 2% reduced fat milk. The viruses used were four enveloped viruses (vesicular … These were sterilized by autoclaving at 121°C for 20 min before each experiment. Despite this, the results from our study showed that during both mechanical and manual ware-washing protocols, chlorine showed little effectiveness in reducing the MNV-1 on the contaminated surfaces. https://doi.org/10.1371/journal.pone.0050273.g005. A three compartment sink manufactured by Eagle Group, Inc. (Clayton, DE), was used for the washing, rinsing and sanitizing of the tableware items. Pamphlet 96, Sodium Hypochlorite Manual, also is available. Tap water was used as a control sanitizer. However, chlorine was able to inactivate both E. coli K-12 and L. innocua. Both Babb and Alvarado et al. Results: Overall, sodium hypochlorite and hydrogen peroxide disinfectants had significantly higher bactericidal efficacies than quaternary ammonium chloride disinfectants. In addition to this, ware-washing protocols that previously showed effectiveness in removing a significant amount of bacteria from contaminated food contact surfaces [10] appear not to have the same efficacy for the removal of viruses. Additionally, the long persistence of norovirus on food preparation surfaces and its resistance to heat and disinfection, make the issue of cross-contamination reduction an even more urgent matter in the fight against foodborne outbreaks [16], [19]. Each cell suspension was separately mixed with the food samples to be tested. Yes 0000010477 00000 n Performed the experiments: LF J. Lee. 0000021358 00000 n No, Is the Subject Area "Norovirus" applicable to this article? Thus, the objective of this study was to evaluate the sanitization efficacy of quaternary ammonium and sodium hypochlorite for the reduction of murine norovirus (a human norovirus surrogate) on different contaminated tableware items using normal ware-washing protocols (manual and mechanical). One could be the food itself. This study evaluated the sanitization efficacies of ware-washing protocols (manual and mechanical) used in restaurants to clean tableware items. Copyright: © 2012 Feliciano et al. Disinfecting is often unnecessary. Efficacies of sodium hypochlorite and quaternary ammonium sanitizers for reduction of norovirus and selected bacteria during ware-washing operations. The plates were incubated at 37°C for 36 h. A Darkfield Colony Counter (American Optical, Buffalo, NY) was used to count the bacterial cells. Yes Most documented foodborne viral outbreaks can be traced to food that has been manually handled by an infected food handler [17]. The forks were washed by using fifteen forward and fifteen backward strokes with the sponge. These researchers also reported that this problem could be compounded if these organisms remain viable on the food contact surface and then go on to form biofilms which act to increase the protection of the microbes against sanitization. Quaternary ammonium, sodium hypochlorite (bleach) and hydrogen peroxide are active ingredients included in the EPA’s list of approved disinfectants to protect against COVID-19 and considered safe to use on our acrylic screens when applied while adhering to these guidelines: The supernatant was decanted and the cell suspension was resuspended in 100 ml of 0.1 M potassium phosphate buffer (pH 7.2) until an initial concentration of approximately 1.0×109 CFU/ml for both E. coli K12 and L. innocua was achieved. However, the mean reductions achieved by the chlorine sanitizer were significantly different (p<0.0001) than those obtained with the control and the QAC. Prior to each experimental run, this dishwasher was thoroughly cleaned with hot water and refilled with fresh water and detergent/sanitizer. The reported values of the viral counts were the mean values of two trials ± standard deviations. All sanitizing solutions during the mechanical ware-washing helped to produce ≥5 log reduction. After incubation, the growth medium was removed and the cell monolayers were infected with 500 µl of each sample dilution. Common foods associated with the transmission of norovirus include fresh produce, ready-to-eat foods, oysters, baked goods, and berries [6]. The effectiveness of chlorine as a sanitizer is also limited by the action of organic matter [31], [32], [33]. The data analyses were performed by the General Linear Model function and Tukey's multiple comparison test with the SAS, version 9.2, statistical program (SAS Institute, Cary, NC) to determine the level of significance between the effect of each sanitizer, tableware item and ware-washing protocol (manual vs. mechanical). During the washing cycle, the tableware items were automatically sprayed with the wash water for 76.5 s at a pressure and temperature of 138 kPa and 49°C, respectively. Under this category, improper cleaning and sanitizing of food-contact surfaces was the item most commonly observed to be out of compliance. Hypochlorous Acid (HOCl) vs. e50273. The reductions achieved by the chlorine and the QAC sanitizers were slightly higher than the ones obtained by the control. Sodium hypochlorite, the active ingredient in chlorine bleach, is routinely used in the laboratory to decontaminate surfaces and equipment or deactivate biological materials by inactivating vegetative bacteria, fungi, lipid and non-lipid viruses, and other liquid specimens. The effect of the ware-washing and sanitizing solutions on the reduction of E. coli K-12 and L. innocua from the contaminated tableware items are also presented in Figs. Exceeding this concentration might have increased the reduction of both test virus and bacteria on the surfaces but could subject consumers to residual toxicity if used in a real world environment. Ceramic plates, drinking glasses and stainless steel forks were used as the food contact surfaces. Fig. The fixation was done for 4 h. The overlay-formaldehyde solution was removed and the wells stained with 0.05% crystal violet (wt/v) for 1 h in order to visualize and count the viral plaques. The plates and glasses were washed by using fifteen clockwise and fifteen counter-clockwise strokes. The mean reductions on the forks and drinking glasses for both organisms ranged between 0 to 0.4 log. The chlorine bleach, containing 6% sodium hypochlorite, was purchased from a local grocery store. The stock culture of each organism was prepared by transferring a loopful of the E. coli and L. innocua into 50 ml of Trypticase soy broth (Difco, Becton Dickinson, Sparks, MD) containing 0.3% (wt/wt) yeast extract (Fisher Scientific) (TSBYE) and then incubation of the cultures at 37°C for 24 h. A loopful of this broth was then inoculated into a Trypticase soy agar slant (Difco, Becton Dickinson) supplemented with 0.3% (wt/wt) yeast extract (TSAYE) and incubated at 37°C for 24 h. This TSAYE containing the cell cultures was stored in a refrigerator at 4°C and used as a stock culture. The concentration used for the Monsoon detergent was 100 ppm. Cross-contamination of ready-to-eat (RTE) foods with pathogens on contaminated tableware and food preparation utensils is an important factor associated with foodborne illnesses. Wrote the paper: LF J. Li MAP. The plates were air dried for 1 h at room temperature (25°C) on a flat, sterile rack prior to the washing protocol. Hence, the hygiene of the personnel who handle food in foodservice establishments is an important preventive measure in minimizing cross-contamination of food contact surfaces and the food itself with norovirus [16], [18]. In light of the recent opinion of the Biocidal Products Committee (BPC) of December 2018 which supported the use of ADBAC/BKC and DDAC for veterinary hygiene (PT 3) and food and feed (PT 4), and thanks to the positive experience gained from the Sodium Hypochlorite Task Force, TEAM mastery and Centro Reach are willing to organise a new Task Force for QUATERNARY AMMONIUM … The same procedure was followed for E. coli K- 12 and L. innocua. The MNV-1 mean reductions achieved with the chlorine sanitizer were statistically (p<0.0001) different than those achieved with the control treatment but not significant (p>0.0001) when compared with those of QAC. There is a great concern regarding the development of antibiotic resistance in Pseudomonas hospital isolates and its possible link to the improper application of commonly used disinfectants.. 0000001748 00000 n 3 and 4. Yes Sodium hypochlorite (chlorine-bleach) and quaternary ammonium compounds (QAC) were used as the sanitizing solutions. 0000002798 00000 n These were contaminated with cream cheese and reduced-fat milk inoculated with murine norovirus (MNV-1), Escherichia coli K-12 and Listeria innocua. After adding the overlay, the plates were placed in a refrigerator (4°C) for 1 h and then incubated at 37°C and 5% CO2 for 2 d. Following this, 2 ml of 10% formaldehyde in PBS solution were added to each well to fix the cells. For contamination of the glasses, 45 ml of milk were transferred to a 50 ml sterile conical tube and inoculated with 5 ml of virus stock solution (1∶10 v/v). To prevent this, restaurants and food service establishments are required to achieve a minimum microbial reduction of 5 logs from these surfaces. The water hardness for both mechanical and manual washing procedures was determined to be less than 120 ppm and it was determined using a Water Quality Test Strip kit (Hach Co., Loveland, CO). 0 �ͽ��ܝM�L j���]=-l%. Comparison of Sodium HypoChlorite. Sodium hypochlorite (chlorine-bleach) and quaternary ammonium compounds (QAC) were used as the sanitizing solutions. After the washing cycle, the tableware items were automatically sprayed with the QAC sanitizing solutions for 10 s at 49°C. No significant differences (p>0.0001) were found for bacterial counts before and after the air-drying period. 0000005841 00000 n 4. These risk factors include: food from unsafe sources; poor personal hygiene; inadequate cooking; improper holding temperatures; and contaminated equipment. Yes