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Morris JN, Esseili MA. Screening Commercial Tea for Rapid Inactivation of Infectious SARS-CoV-2 in Saliva. FOOD AND ENVIRONMENTAL VIROLOGY 2024; 16:159-170. [PMID: 38294673 DOI: 10.1007/s12560-023-09581-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Accepted: 12/30/2023] [Indexed: 02/01/2024]
Abstract
SARS-CoV-2 infects the oral mucosa and is shed in salivary fluids. Traditionally, tea has been used by various cultures to treat respiratory ailments. The objective of this study was to identify commercially available teas that can rapidly inactivate infectious SARS-CoV-2 in saliva. Initially, tea (n = 24) was prepared as 40 mg/mL infusions and incubated with SARS-CoV-2 resuspended in water, for 5 min at 37 °C. Then, five teas that showed >3 log reduction in virus infectivity were further investigated at 40 and 10 mg/mL infusions for 60 and 10 s contact time with SARS-CoV-2 resuspended in saliva. Tea polyphenols were measured using the Folin-Ciocalteu assay. SARS-CoV-2 infectivity was quantified on Vero-E6 cell line using TCID50 assay. At 10 mg/mL infusion, black tea showed the highest reduction (3 log, i.e., 99.9%) of infectious SARS-CoV-2 within 10 s. Green, mint medley, eucalyptus-mint, and raspberry zinger teas showed similar inactivation of SARS-CoV-2 (1.5-2 log, i.e., 96-99% reduction). At 40 mg/mL infusions, all five teas showed >3 log reduction in virus infectivity within 10 s. Tea polyphenol but not pH was significantly correlated to virus reduction. Time-of-addition assay revealed that the five teas displayed preventive effects (0.5-1 log, i.e., 68-90% reduction) against SARS-CoV-2 infection of Vero-E6 cells as well as during post-virus infection (1.2-1.9 log, i.e., 94-98%). However, the highest inhibitory effect was observed when the teas were added at the time of virus infection (2-3 log, i.e., 99-99.9%). Our results provide insights into a rapid at-home intervention (tea drinking or gargling) to reduce infectious SARS-CoV-2 load in the oral cavity which might also mitigate infection of the oral mucosa.
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Affiliation(s)
- Julianna N Morris
- Center for Food Safety, Department of Food Science and Technology, University of Georgia, Griffin Campus, 1109 Experiment Street, Griffin, GA, 30223, USA
| | - Malak A Esseili
- Center for Food Safety, Department of Food Science and Technology, University of Georgia, Griffin Campus, 1109 Experiment Street, Griffin, GA, 30223, USA.
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Olaimat AN, Taybeh AO, Al-Nabulsi A, Al-Holy M, Hatmal MM, Alzyoud J, Aolymat I, Abughoush MH, Shahbaz H, Alzyoud A, Osaili T, Ayyash M, Coombs KM, Holley R. Common and Potential Emerging Foodborne Viruses: A Comprehensive Review. Life (Basel) 2024; 14:190. [PMID: 38398699 PMCID: PMC10890126 DOI: 10.3390/life14020190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Revised: 01/17/2024] [Accepted: 01/26/2024] [Indexed: 02/25/2024] Open
Abstract
Human viruses and viruses from animals can cause illnesses in humans after the consumption of contaminated food or water. Contamination may occur during preparation by infected food handlers, during food production because of unsuitably controlled working conditions, or following the consumption of animal-based foods contaminated by a zoonotic virus. This review discussed the recent information available on the general and clinical characteristics of viruses, viral foodborne outbreaks and control strategies to prevent the viral contamination of food products and water. Viruses are responsible for the greatest number of illnesses from outbreaks caused by food, and risk assessment experts regard them as a high food safety priority. This concern is well founded, since a significant increase in viral foodborne outbreaks has occurred over the past 20 years. Norovirus, hepatitis A and E viruses, rotavirus, astrovirus, adenovirus, and sapovirus are the major common viruses associated with water or foodborne illness outbreaks. It is also suspected that many human viruses including Aichi virus, Nipah virus, tick-borne encephalitis virus, H5N1 avian influenza viruses, and coronaviruses (SARS-CoV-1, SARS-CoV-2 and MERS-CoV) also have the potential to be transmitted via food products. It is evident that the adoption of strict hygienic food processing measures from farm to table is required to prevent viruses from contaminating our food.
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Affiliation(s)
- Amin N. Olaimat
- Department of Clinical Nutrition and Dietetics, Faculty of Applied Medical Sciences, The Hashemite University, P.O. Box 330127, Zarqa 13133, Jordan; (M.A.-H.); (M.H.A.)
| | - Asma’ O. Taybeh
- Department of Nutrition and Food Technology, Faculty of Agriculture, Jordan University of Science and Technology, P.O. Box 3030, Irbid 22110, Jordan; (A.O.T.); (A.A.-N.); (T.O.)
| | - Anas Al-Nabulsi
- Department of Nutrition and Food Technology, Faculty of Agriculture, Jordan University of Science and Technology, P.O. Box 3030, Irbid 22110, Jordan; (A.O.T.); (A.A.-N.); (T.O.)
| | - Murad Al-Holy
- Department of Clinical Nutrition and Dietetics, Faculty of Applied Medical Sciences, The Hashemite University, P.O. Box 330127, Zarqa 13133, Jordan; (M.A.-H.); (M.H.A.)
| | - Ma’mon M. Hatmal
- Department of Medical Laboratory Sciences, Faculty of Applied Medical Sciences, The Hashemite University, P.O. Box 330127, Zarqa 13133, Jordan;
| | - Jihad Alzyoud
- Department of Anatomy, Physiology and Biochemistry, Faculty of Medicine, The Hashemite University, P.O. Box 330127, Zarqa 13133, Jordan; (J.A.); (I.A.)
| | - Iman Aolymat
- Department of Anatomy, Physiology and Biochemistry, Faculty of Medicine, The Hashemite University, P.O. Box 330127, Zarqa 13133, Jordan; (J.A.); (I.A.)
| | - Mahmoud H. Abughoush
- Department of Clinical Nutrition and Dietetics, Faculty of Applied Medical Sciences, The Hashemite University, P.O. Box 330127, Zarqa 13133, Jordan; (M.A.-H.); (M.H.A.)
- Science of Nutrition and Dietetics Program, College of Pharmacy, Al Ain University, Abu Dhabi P.O. Box 64141, United Arab Emirates
| | - Hafiz Shahbaz
- Department of Food Science and Human Nutrition, University of Veterinary and Animal Sciences, Lahore 54000, Pakistan;
| | - Anas Alzyoud
- Faculty of Medicine, The Hashemite University, P.O. Box 330127, Zarqa 13133, Jordan;
| | - Tareq Osaili
- Department of Nutrition and Food Technology, Faculty of Agriculture, Jordan University of Science and Technology, P.O. Box 3030, Irbid 22110, Jordan; (A.O.T.); (A.A.-N.); (T.O.)
- Department of Clinical Nutrition and Dietetics, College of Health Sciences, University of Sharjah, Sharjah P.O. Box 27272, United Arab Emirates
| | - Mutamed Ayyash
- Department of Food Science, College of Agriculture and Veterinary Medicine, United Arab Emirates University, P.O. Box 15551, Al Ain 53000, United Arab Emirates;
| | - Kevin M. Coombs
- Department of Medical Microbiology and Infectious Diseases, Max Rady College of Medicine, University of Manitoba, Winnipeg, MB R3E 0J9, Canada;
| | - Richard Holley
- Department of Food and Human Nutritional Sciences, University of Manitoba, Winnipeg, MB R3T 2N2, Canada;
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Esseili MA. In vitro digestion of SARS-CoV-2 contaminated berries reveals high inactivation of infectious virus during gastrointestinal passage. Appl Environ Microbiol 2023; 89:e0133923. [PMID: 37982639 PMCID: PMC10734541 DOI: 10.1128/aem.01339-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Accepted: 09/28/2023] [Indexed: 11/21/2023] Open
Abstract
IMPORTANCE During the pandemic, news outlets occasionally reported on the detection of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) RNA on various foods, raising concerns over contaminated foods initiating infections. Coronavirus disease 2019 (COVID-19) patients often experience gastrointestinal symptoms and shed SARS-CoV-2 RNA in their feces. In addition, active virus replication in the gastrointestinal tract was shown; however, infectious viruses were rarely detected in feces. We previously showed that SARS-CoV-2 remained infectious on frozen berries for at least a month. Here, in vitro digestion models showed that SARS-CoV-2 on berries exhibits minimal inactivation at the oral phase and the virus may escape gastric inactivation early during feeding. However, high intestinal inactivation of the virus on berries suggested that SARS-CoV-2 was less likely to initiate infection in the small intestine. In contrast, the oral cavity is a potential site where infection might be initiated, providing more input for the gastrointestinal tract. High intestinal inactivation might explain the difficulty of detecting infectious SARS-CoV-2 in feces but not of virus RNA.
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Affiliation(s)
- Malak A. Esseili
- Department of Food Science and Technology, Center for Food Safety, University of Georgia, Griffin, Georgia, USA
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Influence of Bacterial Competitors on Salmonella enterica and Enterohemorrhagic Escherichia coli Growth in Microbiological Media and Attachment to Vegetable Seeds. Foods 2021; 10:foods10020285. [PMID: 33572548 PMCID: PMC7912496 DOI: 10.3390/foods10020285] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 01/19/2021] [Accepted: 01/26/2021] [Indexed: 12/28/2022] Open
Abstract
Interests in using biological agents for control of human pathogens on vegetable seeds are rising. This study evaluated whether probiotic bacterium Lactobacillus rhamnosus GG, bacterial strains previously used as biocontrol agents in plant science, as well as a selected plant pathogen could compete with foodborne human pathogens, such as Salmonella enterica and enterohemorrhagic Escherichia coli (EHEC), for growth in microbiological media and attachment to vegetable seeds; and to determine whether the metabolites in cell-free supernatants of competitive bacterial spent cultures could inhibit the growth of the two pathogens. The results suggest that the co-presence of competitive bacteria, especially L. rhamnosus GG, significantly (p < 0.05) inhibited the growth of Salmonella and EHEC. Cell-free supernatants of L. rhamnosus GG cultures significantly reduced the pathogen populations in microbiological media. Although not as effective as L. rhamnosus GG in inhibiting the growth of Salmonella and EHEC, the biocontrol agents were more effective in competing for attachment to vegetable seeds. The study observed the inhibition of human bacterial pathogens by competitive bacteria or their metabolites and the competitive attachment to sprout seeds among all bacteria involved. The results will help strategize interventions to produce vegetable seeds and seed sprouts free of foodborne pathogens.
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Esseili MA, Gao X, Boley P, Hou Y, Saif LJ, Brewer-Jensen P, Lindesmith LC, Baric RS, Atmar RL, Wang Q. Human Norovirus Histo-Blood Group Antigen (HBGA) Binding Sites Mediate the Virus Specific Interactions with Lettuce Carbohydrates. Viruses 2019; 11:E833. [PMID: 31500340 PMCID: PMC6784273 DOI: 10.3390/v11090833] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Revised: 09/04/2019] [Accepted: 09/06/2019] [Indexed: 12/30/2022] Open
Abstract
Lettuce is often implicated in human norovirus (HuNoV) foodborne outbreaks. We identified H-like histo-blood group antigens (HBGAs) on lettuce leaves as specific binding moieties for virus-like particles (VLPs) of HuNoV GII.4/HS194/2009 strain. The objective of this study was to determine whether HuNoV-lettuce binding is mediated through the virus HBGA binding sites (HBS). Toward this objective, VLPs of historical HuNoV GII.4 strains (1987, 1997, 2002, 2004 and 2006) with known natural mutations in their HBS, two newly generated VLP mutants of GII.4/HS194/2009 (D374A and G443A) and a VLP mutant (W375A) of GI.1/Norwalk/1968 along with its wild type VLPs, which displays distinct HBS, were investigated for their binding to lettuce. ELISA revealed that historical GII.4 strains binding to lettuce was dependent on their HBGAs profiles. The VLP mutants D374A and G443A lost binding to HBGAs and displayed no to minimal binding to lettuce, respectively. The VLPs of GI.1/Norwalk/1968 strain bound to lettuce through an H-like HBGA and the binding was inhibited by fucosidase digestion. Mutant W375A which was previously shown not to bind to HBGAs, displayed significantly reduced binding to lettuce. We conclude that the binding of HuNoV GII.4 and GI.1 strains to lettuce is mediated through the virus HBS.
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Affiliation(s)
- Malak A Esseili
- Food Animal Health Research Program, Ohio Agricultural Research and Development Center, Department of Veterinary Preventive Medicine, The Ohio State University, Wooster, OH 44691, USA.
- Currently at Center for Food Safety, Department of Food Science and Technology, University of Georgia, Griffin, GA 30223, USA.
| | - Xiang Gao
- Food Animal Health Research Program, Ohio Agricultural Research and Development Center, Department of Veterinary Preventive Medicine, The Ohio State University, Wooster, OH 44691, USA.
| | - Patricia Boley
- Food Animal Health Research Program, Ohio Agricultural Research and Development Center, Department of Veterinary Preventive Medicine, The Ohio State University, Wooster, OH 44691, USA.
| | - Yixuan Hou
- Food Animal Health Research Program, Ohio Agricultural Research and Development Center, Department of Veterinary Preventive Medicine, The Ohio State University, Wooster, OH 44691, USA.
| | - Linda J Saif
- Food Animal Health Research Program, Ohio Agricultural Research and Development Center, Department of Veterinary Preventive Medicine, The Ohio State University, Wooster, OH 44691, USA.
| | - Paul Brewer-Jensen
- Department of Epidemiology, University of North Carolina, Chapel Hill, NC 27599-7435, USA.
| | - Lisa C Lindesmith
- Department of Epidemiology, University of North Carolina, Chapel Hill, NC 27599-7435, USA.
| | - Ralph S Baric
- Department of Epidemiology, University of North Carolina, Chapel Hill, NC 27599-7435, USA.
| | - Robert L Atmar
- Department of Molecular Virology and Microbiology and Department of Medicine, Baylor College of Medicine, Houston, TX 77030, USA.
| | - Qiuhong Wang
- Food Animal Health Research Program, Ohio Agricultural Research and Development Center, Department of Veterinary Preventive Medicine, The Ohio State University, Wooster, OH 44691, USA.
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Esseili MA, Meulia T, Saif LJ, Wang Q. Tissue Distribution and Visualization of Internalized Human Norovirus in Leafy Greens. Appl Environ Microbiol 2018; 84:e00292-18. [PMID: 29625983 PMCID: PMC5981073 DOI: 10.1128/aem.00292-18] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2018] [Accepted: 04/03/2018] [Indexed: 12/21/2022] Open
Abstract
Lettuce has been implicated in human norovirus (HuNoV) outbreaks. The virus is stable on the leaf surface for at least 2 weeks; however, the dynamics of virus internalization have not been fully investigated. The purpose of this study was to assess the internalization and distribution of HuNoV and two surrogate viruses, porcine sapovirus (SaV) and Tulane virus (TV), in lettuce and spinach. Viral inoculations through the roots of seedlings and the petiole of leaves from mature plants were performed, and the viruses were tracked on days 1 and 6 post-root inoculation and at 16 h and 72 h post-petiole inoculation. Confocal microscopy was used to visualize root-internalized HuNoV. In both lettuce and spinach, (i) HuNoV was internalized into the roots and leaves at similar RNA titers, whereas surrogate viruses were more restricted to the roots, (ii) all three viruses were stable inside the roots and leaves for at least 6 days, and (iii) HuNoV disseminated similarly inside the central veins and leaf lamina, whereas surrogate viruses were more restricted to the central veins. Infectious TV, but not SaV, was detectable in all tissues, suggesting that TV has greater stability than SaV. HuNoV was visualized inside the roots' vascular bundle and the leaf mesophyll of both plants. In conclusion, using surrogate viruses may underestimate the level of HuNoV internalization into edible leaves. The internalization of HuNoV through roots and cut leaves and the dissemination into various spinach and lettuce tissues raise concerns of internal contamination through irrigation and/or wash water.IMPORTANCE Human noroviruses are the leading cause of foodborne outbreaks, with lettuce being implicated in the majority of outbreaks. The virus causes acute gastroenteritis in all age groups, with more severe symptoms in children, the elderly, and immunocompromised patients, contributing to over 200,000 deaths worldwide annually. The majority of deaths due to HuNoV occur in the developing world, where limited sanitation exists along with poor wastewater treatment facilities, resulting in the contamination of water resources that are often used for irrigation. Our study confirms the ability of lettuce and spinach to internalize HuNoV from contaminated water through the roots into the edible leaves. Since these leafy greens are consumed with minimal processing that targets only surface pathogens, the internalized HuNoV presents an added risk to consumers. Thus, preventive measures should be in place to limit the contamination of irrigation water. In addition, better processing technologies are needed to inactivate internalized viral pathogens.
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Affiliation(s)
- Malak A Esseili
- Food Animal Health Research Program, Ohio Agricultural Research and Development Center, College of Food Agriculture and Environmental Sciences, Department of Veterinary Preventive Medicine, The Ohio State University, Wooster, Ohio, USA
| | - Tea Meulia
- Molecular and Cellular Imaging Center, Ohio Agricultural Research and Development Center, The Ohio State University, Wooster, Ohio, USA
| | - Linda J Saif
- Food Animal Health Research Program, Ohio Agricultural Research and Development Center, College of Food Agriculture and Environmental Sciences, Department of Veterinary Preventive Medicine, The Ohio State University, Wooster, Ohio, USA
| | - Qiuhong Wang
- Food Animal Health Research Program, Ohio Agricultural Research and Development Center, College of Food Agriculture and Environmental Sciences, Department of Veterinary Preventive Medicine, The Ohio State University, Wooster, Ohio, USA
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Gao X, Esseili MA, Lu Z, Saif LJ, Wang Q. Recognition of Histo-Blood Group Antigen-Like Carbohydrates in Lettuce by Human GII.4 Norovirus. Appl Environ Microbiol 2016; 82:2966-74. [PMID: 26969699 PMCID: PMC4959087 DOI: 10.1128/aem.04096-15] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Accepted: 03/03/2016] [Indexed: 01/20/2023] Open
Abstract
UNLABELLED Human norovirus (HuNoV) genogroup II genotype 4 (GII.4) strains account for about 80% of the gastroenteritis outbreaks in the United States. Contaminated food is a major transmission vehicle for this virus. In humans, pigs, and oysters, histo-blood group antigens (HBGAs) act as attachment factors for HuNoVs. In lettuce, although the virus-like particles (VLPs) of a GII.4 HuNoV were found to bind to cell wall carbohydrates, the exact binding site has not been investigated. Here, we show the presence of HBGA-like carbohydrates in the cell wall of lettuce. The digestion of lettuce leaves with cell wall-degrading enzymes exposed more binding sites and significantly increased the level of binding of GII.4 HuNoV VLPs. Competition assays showed that both the HBGA monoclonal antibody, recognizing the H type, and plant lectins, recognizing α-l-fucose in the H type, effectively inhibited VLP binding to lettuce tissues. Lettuce cell wall components were isolated and their NoV VLP binding characteristics were tested by enzyme-linked immunosorbent assays. The binding was inhibited by pretreatment of the lettuce cell wall materials with α-1,2-fucosidase. Collectively, our results indicate that H-type HBGA-like carbohydrates exist in lettuce tissues and that GII.4 HuNoV VLPs can bind the exposed fucose moiety, possibly in the hemicellulose component of the cell wall. IMPORTANCE Salad crops and fruits are increasingly recognized as vehicles for human norovirus (HuNoV) transmission. A recent study showed that HuNoVs specifically bind to the carbohydrates of the lettuce cell wall. Histo-blood group antigens (HBGAs) are carbohydrates and are known as the attachment factors for HuNoV infection in humans. In this study, we show the presence of HBGA-like carbohydrates in lettuce, to which HuNoVs specifically bind. These results suggest that specifically bound HuNoVs cannot be removed by simple washing, which may allow viral transmission to consumers. Our findings provide new information needed for developing potential inhibitors to block binding and prevent contamination.
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Affiliation(s)
- Xiang Gao
- Food Animal Health Research Program, Ohio Agricultural Research and Development Center, Department of Veterinary Preventive Medicine, The Ohio State University, Wooster, Ohio, USAFDA Center for Food Safety and Applied Nutrition
| | - Malak A Esseili
- Food Animal Health Research Program, Ohio Agricultural Research and Development Center, Department of Veterinary Preventive Medicine, The Ohio State University, Wooster, Ohio, USAFDA Center for Food Safety and Applied Nutrition
| | - Zhongyan Lu
- Food Animal Health Research Program, Ohio Agricultural Research and Development Center, Department of Veterinary Preventive Medicine, The Ohio State University, Wooster, Ohio, USAFDA Center for Food Safety and Applied Nutrition
| | - Linda J Saif
- Food Animal Health Research Program, Ohio Agricultural Research and Development Center, Department of Veterinary Preventive Medicine, The Ohio State University, Wooster, Ohio, USAFDA Center for Food Safety and Applied Nutrition
| | - Qiuhong Wang
- Food Animal Health Research Program, Ohio Agricultural Research and Development Center, Department of Veterinary Preventive Medicine, The Ohio State University, Wooster, Ohio, USAFDA Center for Food Safety and Applied Nutrition
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Esseili MA, Gao X, Tegtmeier S, Saif LJ, Wang Q. Abiotic Stress and Phyllosphere Bacteria Influence the Survival of Human Norovirus and Its Surrogates on Preharvest Leafy Greens. Appl Environ Microbiol 2016; 82:352-63. [PMID: 26497461 PMCID: PMC4702653 DOI: 10.1128/aem.02763-15] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Accepted: 10/21/2015] [Indexed: 12/27/2022] Open
Abstract
Foodborne outbreaks of human noroviruses (HuNoVs) are frequently associated with leafy greens. Because there is no effective method to eliminate HuNoV from postharvest leafy greens, understanding virus survival under preharvest conditions is crucial. The objective of this study was to evaluate the survival of HuNoV and its surrogate viruses, murine norovirus (MNV), porcine sapovirus (SaV), and Tulane virus (TV), on preharvest lettuce and spinach that were subjected to abiotic stress (physical damage, heat, or flood). We also examined the bacteria culturable from the phyllosphere in response to abiotic stress and in relation to viral persistence. Mature plants were subjected to stressors 2 days prior to inoculation of the viruses on leaves. We quantified the viral RNA, determined the infectivity of the surrogates, and performed bacterial counts on postinoculation days (PIDs) 0, 1, 7, and 14. For both plant types, time exerted significant effects on HuNoV, MNV, SaV, and TV RNA titers, with greater effects being seen for the surrogates. Infectious surrogate viruses were undetectable on PID 14. Only physical damage on PID 14 significantly enhanced HuNoV RNA persistence on lettuce, while the three stressors differentially enhanced the persistence of MNV and TV RNA. Bacterial counts were significantly affected by time and plant type but not by the stressors. However, bacterial counts correlated significantly with HuNoV RNA titers on spinach and with the presence of surrogate viruses on both plant types under various conditions. In conclusion, abiotic stressors and phyllosphere bacterial density may differentially influence the survival of HuNoV and its surrogates on lettuce and spinach, emphasizing the need for the use of preventive measures at the preharvest stage.
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Affiliation(s)
- Malak A Esseili
- Food Animal Health Research Program, Ohio Agricultural Research and Development Center, Department of Veterinary Preventive Medicine, The Ohio State University, Wooster, Ohio, USA
| | - Xiang Gao
- Food Animal Health Research Program, Ohio Agricultural Research and Development Center, Department of Veterinary Preventive Medicine, The Ohio State University, Wooster, Ohio, USA
| | - Sarah Tegtmeier
- Food Animal Health Research Program, Ohio Agricultural Research and Development Center, Department of Veterinary Preventive Medicine, The Ohio State University, Wooster, Ohio, USA
| | - Linda J Saif
- Food Animal Health Research Program, Ohio Agricultural Research and Development Center, Department of Veterinary Preventive Medicine, The Ohio State University, Wooster, Ohio, USA
| | - Qiuhong Wang
- Food Animal Health Research Program, Ohio Agricultural Research and Development Center, Department of Veterinary Preventive Medicine, The Ohio State University, Wooster, Ohio, USA
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