Source: OHIO STATE UNIVERSITY submitted to NRP
AN INTEGRATED APPROACH TO PREVENT AND MINIMIZE FOODBORNE ENTERIC VIRUSES IN VEGETABLES AND FRUITS
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
COMPLETE
Funding Source
OTHER GRANTS
Reporting Frequency
Annual
Accession No.
0222209
Grant No.
2010-51110-21080
Cumulative Award Amt.
$1,000,000.00
Proposal No.
2010-01498
Multistate No.
(N/A)
Project Start Date
Sep 1, 2010
Project End Date
Aug 31, 2015
Grant Year
2010
Program Code
[111]- National Integrated Food Safety Initiative
Recipient Organization
OHIO STATE UNIVERSITY
1680 MADISON AVENUE
WOOSTER,OH 44691
Performing Department
Food Science & Technology
Non Technical Summary
This special emphasis NIFSI project directly addresses the most prevalent cause of food illness with a strategy to prevent and minimize the foodborne enteric viruses in vegetables and fruits. Foodborne viruses are the dominant causative agents of fresh produce associated disease outbreaks. However, the ecology and survival of enteric viruses in fresh produce is poorly understood. None of the decontamination methods investigated so far have been shown to effectively eliminate foodborne viruses in fresh produce. No major extension and outreach effort has focused on the highly relevant challenge of virus contamination in fresh produce. In this project, we propose an integrated approach to prevent and minimize the foodborne enteric viruses in vegetables and fruits. Using cultivable murine norovirus and hepatitis A virus as the models, we will determine the attachment, internalization, and survival of foodborne viruses in vegetables and fruits, and develop novel sanitizers and non-thermal processing technologies to remove and inactivate enteric viruses in fresh produce. Our extension effort will focus on disseminating these new knowledge and practices to stakeholders and the fresh produce industry with a goal of improving practice and implementing these new preventive strategies and interventions. Furthermore, we will incorporate these new knowledge and practices into the higher education system, develop Foodborne Viruses and Food Safety and Food Virus Education Module, and train the next generation of food safety professionals in the US. Our project will not only fill a major gap in our understanding of the interaction of virus and fresh produce, but also will result in the development and implementation of novel strategies and interventions to prevent and minimize the foodborne viruses. In the long term, our efforts will improve the safety of vegetables and fruits through integration of research, extension, and education.
Animal Health Component
90%
Research Effort Categories
Basic
(N/A)
Applied
90%
Developmental
10%
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
7121430110160%
7121451110120%
7121122110120%
Knowledge Area
712 - Protect Food from Contamination by Pathogenic Microorganisms, Parasites, and Naturally Occurring Toxins;

Subject Of Investigation
1430 - Greens and leafy vegetables; 1122 - Strawberry; 1451 - Onion, garlic, leek, shallot;

Field Of Science
1101 - Virology;
Goals / Objectives
The overall goals of this project are to understand the attachment, internalization, and survival of foodborne viruses in vegetables and fruits, to develop novel sanitization and process technologies to inactivate the viruses, and to minimize virus contamination in fresh produce via extension, outreach and education programs. Our approach is to use cultivable murine norovirus (NoV) and hepatitis A virus (HAV) as models to study the human enteric viruses. Specific objectives are (1) to determine whether NoV and HAV are internalized via the root and/or the surface of vegetables and fruits; (2) to determine the dynamics of NoV and HAV attachment to fresh produce and to determine the rate of transfer from hands, contact surfaces, and packaging materials to vegetables and fruits; (3) to determine the effectiveness of different sanitizers on removing enteric viruses from vegetables and fruits; (4) to determine the efficiency of non-thermal processing technologies on inactivating NoV and HAV on the surface or internalized in vegetables and fruits; (5) to prevent and minimize virus contamination in vegetables and fruits by integrating research, extension, and outreach programs in multiple states; and (6) to develop a "Foodborne Viruses and Food Safety" course and food virus module for classroom education on the nation's leading cause of food illness. Upon the completion of this project, we expect that (1) we will have demonstrated NoV and HAV are internalized in vegetables and fruits; (2) we will have determined the efficiency of virus attachment to fresh produce; (3) we will have demonstrated that viruses can be effectively removed and/or inactivated using new sanitizers and emerging food processing technologies; (4) we will have developed excellent workshops and education materials to train the target audiences; (5) the target audience will have a significant practice and behavior change in minimizing the foodborne viruses contamination; and (6) we will have developed "Foodborne Viruses and Food Safety" course and food virus module to train undergraduates, graduate students, food safety educators, public health experts, and extension professionals.
Project Methods
We will use cultivable murine norovirus (NoV) and hepatitis A virus (HAV) as models to understand the attachment, internalization, and survival of foodborne viruses in vegetables and fruits, to develop novel sanitization and process technologies to inactivate the viruses, and to minimize virus contamination in fresh produce via extension, outreach and education programs. Hepatitis A virus will be propagated in fetal rhesus monkey kidney (FRhK-4) cells. Murine norovirus will grow in murine macrophage (RAW 264.7) cells. To determine the dynamics of virus attachment to fresh produce, NoV and HAV will be inoculated onto lettuce and strawberries, mixed and rinsed by distilled water with gentle agitation, and the remaining viruses in fresh produce will be quantified by plaque assay. Subsequently, we will determine the efficiency of virus transfer from hands, contact surfaces, and packaging materials to vegetables and fruits. To investigate the viral internalization in plant tissue, we will use the following virus-food combinations: HAV-green onions and NoV-lettuce. The actively growing lettuce and green onion will be inoculated with NoV and HAV respectively. The internalized viruses will be quantified by real-time RT-PCR. The internalized viruses will be visualized using confocal or transmission electron microscopes. To develop novel sanitization methods for removing viruses from fresh produce, we will systematically screen effective sanitizer(s) by combination of various sanitizers and/or surfactants. To inactivate the internalized viruses in vegetables and fruits, we propose to use two non-thermal processing technologies (E-beam and high pressure processing). Our extension and outreach effort will focus on disseminating these new knowledge and practices to stakeholders and the fresh produce industry with a goal of improving practice and implementing these new preventive strategies and interventions. Our education effort will focus on developing a "Foodborne Viruses and Food Safety" course and food virus module for classroom education on the nation's leading cause of food illness Our proposed research will fill a major gap in our understanding of the ecology and survival of foodborne enteric viruses in fresh produce. This knowledge is needed to make possible the development and extension of effective preventive innovations. This project will also result in the development of practical ways to inactivate these viruses with approved technologies and use our existing industry network to ensure consumer food safety. In the long-term, our effort will improve food safety and public health.

Progress 09/01/10 to 08/31/15

Outputs
Target Audience:The target audiences for this project are university graduate students, undergraduate students, post-doctoral researchers, visiting scholars, researchers in food virology and food safety, small and medium sized farmers, fresh produce grower, packers, processors, and food safety workers and extension agents. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?This project provides a unique opportunity for students to experience a multidisciplinary effort. Graduate students, undergraduate students, post-docs, and technicians from all five collaborative institutions participate in this project have become experts in the areas of food virology, food safety, fresh produce processing, and nonthermal processing technologies. Three people working on this project have obtained faculty positions at US universities. For example, PD Dr. Jianrong Li's Ph.D. student (Erin DiCaprio) accepted a Tenure Track Assistant Professor position in the Department of Food Science at University of California-Davis and is developing a food virology program in the campus. Co-PD Dr. Haiqiang Chen's post-doc (Dr. Xinhui Li) becomes an Assistant Professor at University of Wisconsin- Lacrosse, developed a food virology and food processing program. 8 graduate students trained from this project now accepted food safety position in major food companies focusing on non-thermal food processing technologies and food safety. In addition, there are a total of 11 undergraduate students in food science major or public health major directly involved in this project. After receiving BS degree, they became graduate students in food safety and food virology or employed in food industry. One important outcome of this project is the development courses on food virology, food safety and food processing. The two courses "Foodborne Viruses and Food Safety "Advanced Food Microbiology-Food Virology and Immunology" have trained 40 students each year in classroom environment. The Food Virology module developed in this project has been incorporated into major food science and public health courses including Food Microbiology, Food Safety, Innovative Food Processing and Preservation Technologies course, and Food Engineering. Undergraduate students and graduate students from all participating institutions received food virology education. How have the results been disseminated to communities of interest?This project yielded critical information of minimizing the foodborne enteric virus contamination in fresh produce and identified several sanitizers and nonthermal processing technologies that can effectively inactivate foodborne viruses. The research findings of this project will be published in peer-reviewed journals such as Applied and Environmental Microbiology, Journal of Food Protection, Food Microbiology, International Journal of Food Microbiology, and Annual Review of Food Science and Technology. The findings from this project have been presented at national professional meetings, including American Society for Virology conference, International Conference on Calicivirus, Institute of Food Technologists (IFT), International Association for Food Protection (IAFP), Ohio Association of Food Protection, Ohio-Indiana-Michigan Tri-state Food Safety Conference. We also organized two symposiums on non-thermal food processing technologies and human norovirus at the 2015 IFT Annual Meeting. One of major task of our extension is to disseminate the outcomes from this project to target audiences which include small and medium sized farmers, fresh produce grower-packers and fresh produce processors, and County Food Safety Extension Agents at all participating institutions. : A series of workshops and trainings have been conducted in participating states for the target audiences. In addition, the team has been closely working with a number of industry partners, for example, Center for Advanced Processing and Packaging Studies (CAPPS), which includes 10 food companies such as Nestle, Kraft Foods, HP Hood LLC; Hormel Foods; Dr Pepper Snapple Group; J.M. Smucker Company; Michael Foods, Inc.; Abbott Nutrition; Coca-Cola; AFP advanced food products LLC. In the past 5 years, our team has trained approximately 3,000 farmers, fresh produce grower, packers, processors, employees from food industry, and food safety workers. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Enteric viruses cause more than 60% of foodborne illnesses in the United States. Among those commonly known are human norovirus (NoV) and hepatitis A virus (HAV). Particularly, human NoV is responsible for more than 90% of outbreaks of acute nonbacterial gastroenteritis. Unfortunately, fresh produce is one of major high risk food for enteric virus contamination. Increasing outbreaks of viruses in fresh and fresh-cut vegetables and fruits gives high urgency to our plan to eliminate enteric viruses in vegetables and fruits. After 5 years hard work, this project delivered a number of high impact results, technologies and interventions in minimizing enteric foodborne viruses in fresh produce. First, this project filled a major gap in our understanding of the ecology and survival of foodborne enteric viruses in fresh produce. Second, this project significantly increased our knowledge on the attachment, penetration, uptake, internalization, dissemination, and persistence of foodborne viruses in fresh produce. Third, this project identified several novel sanitizers that enhanced removal of foodborne viruses from fresh produce. Fourth, this project identified several nonthermal processing technologies that are capable of inactivating foodborne viruses in fresh produce. Fifth, this project delivered and disseminated important knowledge and preventive practices on foodborne viruses to target audiences and stakeholders. Finally, this project developed "Foodborne Viruses and Food Safety" course and "Food Virus Education Module", and incorporated foodborne viruses into the food safety education system and trained the next generation of food safety professionals in the US. We have a total of six Specific Objectives. Major accomplishments are summarized as followings. Objective 1 is to determine whether NoV and HAV are internalized via the root and/or the surface of vegetables and fruits. We found that human NoV, its surrogates (murine norovirus, MNV-1), and HAV can be efficiently internalized via roots and disseminated to edible portions (shoots and leaves) of the plant grown hydroponically (DiCaprio et al., Applied and Environmental Microbiology, 2012) and in soil condition. We also demonstrated for the first time that abiotic stress (drought) but not biotic stress (LMV infection) affects the rates of viral internalization and dissemination, and the type of virus affects the efficiency of internalization and dissemination (DiCaprio et al., Applied and Environmental Microbiology, 2015a). Furthermore, we demonstrated for the first time that virally contaminated soils can lead to the internalization of virus via plant roots and subsequent dissemination to the leaf and fruit portions of growing strawberry plants and the magnitude of internalization is dependent on the type of virus and plant (DiCaprio et al., Applied and Environmental Microbiology, 2015b). This finding was selected as a "spotlight" by the editors of Applied and Environmental Microbiology, one of the top journals in food safety. Objective 2 is to determine the dynamics of NoV and HAV attachment to fresh produce and to determine the rate of transfer from hands, contact surfaces, and packaging materials to vegetables and fruits. We determined the attachment of human NoV, MNV-1; Tulane virus (TV), and HAV to fresh produce was evaluated, using both visualization and viral enumeration techniques. We found that a human NoV strain attached efficiently to the Romaine lettuce leaves and roots and green onion shoots. It was found that human NoV virus-like particles (VLPs), TV, and MNV-1 associated with the surface of Romaine lettuce and were found aggregating in and around the stomata. In green onions, human NoV VLPs were found between the cells of the epidermis and cell walls of both the shoots and roots. However, TV and MNV-1 were found to be covering the surface of the epidermal cells in both the shoots and roots of green onions. In addition, we found that foodborne viruses efficiently transferred from hands, contact surfaces, and packaging materials to vegetables and fruits. These findings were published in International Journal of Food Microbiology (DiCaprio et al., 2015) and Applied and Environmental Microbiology (Liu et al., 2010). The Objective 3 is to determine the effectiveness of different sanitizers on removing enteric viruses from vegetables and fruits. To this end, we found that combination of surfactants (sodium dodecyl sulfate (SDS), Nonidet P-40 (NP-40), Triton X-100, and polysorbates) and sanitizers (200 ppm chlorine) can enhance the removal of human NoV and other enteric virus from fresh vegetables and fruits by approximately 100 times. Implementation of this novel sanitization strategy would be a feasible approach for efficient reduction of the virus load in fresh produce. This work has been published in Applied and Environmental Microbiology (Predmore et al., 2011). A patent entitled "A strategy to enhance the sanitization of foodborne viruses in fresh produce" has been filed (patent no. WO2012118789). In addition, we found that gaseous ozone inactivated norovirus in both liquid media and fresh produce in a dose-dependent manner (Predmore et al., Food Microbiology, 2015) Objective 4 is to determine the efficiency of non-thermal processing technologies on inactivating NoV and HAV on the surface or internalized in vegetables and fruits. We next determined two non-thermal processing technologies (E-beam, and high pressure processing, HPP) to inactivate internalized viruses in vegetables and fruits. We demonstrated that human NoV surrogates (MNV-1) was effectively inactivated by HPP. More than a 5-log-PFU/g reduction was achieved in all tested fresh produce when it was pressurized at 400 MPa for 2 min at 4°C. HPP had a minimal impact on food quality and thus can provide a novel intervention for processing fruits intended for frozen storage and related products (Lou et al., Applied and Environmental Microbiology, 2011a). We also demonstrated that HPP is capable of effectively inactivating other foodborne viruses (such as HAV, and rotavirus) (Lou et al., Applied and Environmental Microbiology, 2011b). However, we found that major foodborne viruses are resistant to E-beam technologies. We found that, under FDA-approved irradiation dose limits (4 kGy), only 1-2 log virus reduction was achieved (Sanglay et al., Journal of Food Protection, 2011; Predmore et al., International of Journal of Food Microbiology, 2015). Objective 5 is to prevent and minimize virus contamination in vegetables and fruits by integrating research, extension, and outreach programs in multiple states. The extension activities were led by two co-PIs, Professor Douglas Doohan (Director of OSU Extension Fresh Fruit and Vegetable Food Safety Team) and Professor Ken Lee (Director of Food Innovation Center at OSU). The workshop of our extension includes knowledge-increasing activities and skill development in an applied, on-farm or in a packing facility situation. In the past 5 years, Dr. Doohan's team has trained approximately 3,000 farmers, fresh produce grower, packers, fresh produce processors, county food safety extension agents, employees from food industry, and food safety workers. Objective 6 is to develop a "Foodborne Viruses and Food Safety" course and food virus module for classroom education on the nation's leading cause of food illness. At year 2, the PD has developed "Foodborne Viruses and Food Safety" for undergraduate and "Advanced Food Microbiology-Food Virology and Immunology" for graduate students. Each year, 30-40 students were enrolled these two classes. In addition, the co-PDs have incorporated Food Virology Modules into their courses including Innovative Food Processing and Preservation Technologies course, Food Engineering course at University of Delaware, Food Microbiology courses at North Carolina State University.

Publications

  • Type: Journal Articles Status: Published Year Published: 2010 Citation: Liu P, Yuen Y, Hsiao HM, Jaykus LA, Moe C. Effectiveness of liquid soap and hand sanitizer against Norwalk virus on contaminated hands. Appl Environ Microbiol. 2010 Jan;76(2):394-9.
  • Type: Journal Articles Status: Published Year Published: 2016 Citation: Huang R, Ye M, Li X, Ji L, Karwe M, Chen H. Evaluation of high hydrostatic pressure inactivation of human norovirus on strawberries, blueberries, raspberries and in their purees. Int J Food Microbiol. 2016 Apr 16;223:17-24.
  • Type: Journal Articles Status: Published Year Published: 2014 Citation: Huang R, Li X, Huang Y, Chen H. Strategies to enhance high pressure inactivation of murine norovirus in strawberry puree and on strawberries. Int J Food Microbiol. 2014 Aug 18;185:1-6.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2011 Citation: Elbashir Araud, and Jianrong Li. "Distribution and inactivation of a human norovirus surrogate and hepatitis A virus in oyster." [Abstract]. International Association of Food Protection. Milwaukee, WI. July 2011.
  • Type: Journal Articles Status: Published Year Published: 2012 Citation: Li, D., Baert, L., Zhong, D., Xia, M., Zhong, W., Van Coillie, E., and Jiang, X. The Effect of grape seed extract on human noroviruses GII.4 and murine norovirus-1 in viral suspensions, on stainless steel discs, and in lettuce wash water. Appl. Environ. Microbiol. 2012. 78: 7572-7578.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2012 Citation: Elbashir Araud, Fangfei Lou, Xinhui Li, Haiqiang Chen, and Jianrong Li. "High pressure processing of rotaviruses: the roles of strain diversity and treatment temperature in virus inactivation." [Abstract]. International Association of Food Protection. Providence, RI. July. 2012
  • Type: Conference Papers and Presentations Status: Published Year Published: 2012 Citation: Erin DiCaprio, Yuanmei Ma, Anastasia Purgianto, John Hughes, and Jianrong Li. "Attachment, internalization, and dissemination of human norovirus surrogates in Romaine lettuce." [Abstract]. International Association of Food Protection. Providence, RI. July 2012.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2012 Citation: Fangfei Lou, Pengwei Huang, Hudaa Neetoo, Joshua B. Gurtler, Brendan A. Niemira, Haiqiang Chen, Xi Jiang, and Jianrong Li. "High pressure inactivation of human norovirus virus-like particles: evidence that human norovirus may be highly pressure resistant." [Abstract]. International Association of Food Protection. Providence, RI. July, 2012.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2012 Citation: Haiqiang Chen, Jianrong Li. "Control of food noroviruses using non-thermal processes and applications for high-risk foods." [Abstract]. Institute of Food Technologists. Las Vegas. June 2012
  • Type: Conference Papers and Presentations Status: Published Year Published: 2012 Citation: Jianrong Li. "High pressure inactivation of human norovirus in foods and environment." [Abstract]. International Conference for Chemical Engineering. Ixatapa: Mexico. March 2012.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2011 Citation: Ashley Predmore, and Jianrong Li. "Enhanced removal of noroviruses from fresh fruits and vegetables by combination of surfactants and organic acids." [Abstract]. International Association of Food Protection. Milwaukee, WI. July, 2011.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2011 Citation: Kurtis Feng, Erin Divers, Yuanmei Ma, and Jianrong Li. "Inactivation of human norovirus surrogate, human norovirus virus-like particle, and vesicular stomatitis virus by gamma irradiation: sensitivity and mechanism." [Abstract]. International Association of Food Protection. Milwaukee, WI. July 2011.
  • Type: Journal Articles Status: Published Year Published: 2011 Citation: Fangfei Lou, Hudaa Needoo, Haiqiang Chen, Jianrong Li. Inactivation of human norovirus surrogate by high pressure processing: effectiveness, mechanism and potential application in fresh produce industry. Applied and Environmental Microbiology. 2011, 77(5): 1862-1871.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2010 Citation: Ashley Predmore, Claire Herbert, and Jianrong Li. "Enhanced removal of Noroviruses from fresh fruits and vegetables by combination of surfactants and sanitizers." [Abstract]. International Association of Food Protection. Anaheim, CA. Aug 2010.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2010 Citation: Fangfei Lou, Hudaa Neetoo, Haiqiang Chen, and Jianrong Li. "High pressure inactivation of noroviruses in vegetables and fruits." [Abstract]. International Association of Food Protection. Anaheim, CA. Aug 2010.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2010 Citation: Gabriel Sanglay, Jianrong Li, and Ken Lee. "Electron-Beam inactivation of a norovirus surrogate." [Abstract]. Institute of Food Technologists. Chicago, IL. July, 2010.
  • Type: Journal Articles Status: Published Year Published: 2011 Citation: Gabriel Sanglay, Jianrong Li, Roberto Uribe, Ken Lee. Electron beam inactivation of a norovirus surrogate in fresh produce and model system. Journal of Food Protection. 2011, 74(7):1155-60.
  • Type: Journal Articles Status: Published Year Published: 2011 Citation: Fangfei Lou, Hudaa Needoo, Junan Li, Haiqiang Chen, Jianrong Li. Lack of correlation between virus barosensitivity and the presence of a viral envelope during inactivation of human rotavirus, vesicular stomatitis virus, and avian metapneumovirus by high-pressure processing. Applied and Environmental Microbiology. 2011, 24 (77): 8538-8547.
  • Type: Journal Articles Status: Published Year Published: 2011 Citation: Ashley Predmore, Jianrong Li. 2011. Enhanced Sanitization of a Human Norovirus Surrogate in Fresh Vegetables and Fruits by a Combination of Surfactants and Sanitizers. Applied and Environmental Microbiology. 2011, 77(14):4829-4838.
  • Type: Journal Articles Status: Published Year Published: 2011 Citation: Kurtis Feng, Erin Divers, Yuanmei Ma, Jianrong Li. Inactivation of human norovirus surrogate, human norovirus virus-like particle, and vesicular stomatitis virus by gamma irradiation. Applied and Environmental Microbiology. 2011, 77 (10): 3507-3517.
  • Type: Journal Articles Status: Published Year Published: 2012 Citation: Fangfei Lou, Pengwei Huang, Hudaa Neetoo, Joshua Gurtler, Brendan Niemira, Haiqiang Chen, Xi Jiang, Jianrong Li. High pressure inactivation of human norovirus virus-like particles: evidence that the capsid of human norovirus is highly pressure resistant. Applied and Environmental Microbiology 2012, 78(15):5320-5327.
  • Type: Journal Articles Status: Published Year Published: 2012 Citation: Jianrong Li, Ashley Predmore, Erin Divers, Fangfei Lou. New interventions against human norovirus: progress, opportunities, and challenges. Annual Review of Food Science and Technology, 2012, 3: 331-352.
  • Type: Journal Articles Status: Published Year Published: 2012 Citation: Erin DiCaprio, Yuanmei Ma, John Hughes, Jianrong Li. Internalization and dissemination of human norovirus and animal caliciviruses in hydroponically grown Romaine lettuce. Applied and Environmental Microbiology. 2012, 78(17):6143-6152.
  • Type: Journal Articles Status: Published Year Published: 2013 Citation: Erin Dicaprio, Yuanmei Ma, John Hughes, Jianrong Li. Epidemiology, prevention, and control of the number one foodborne illness: human norovirus. Infectious Diseases Clinics of North America. 2013, 27(3):651-74.
  • Type: Journal Articles Status: Published Year Published: 2014 Citation: Ge C, Lee C, Nangle E, Jianrong Li, Gardner D, Kleinhenz M, Lee J. Impact of phytopathogen infection and extreme weather stress on internalization of Salmonella Typhimurium in lettuce. International Journal of Food Microbiology, 2014, 168:24-31.
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Jia Wei Yeap, Simran Kaur, Fangfei Lou, Erin DiCaprio, Mark Morgan, Richard Linton, and Jianrong Li. Inactivation kinetics and mechanism of a human norovirus surrogate on stainless steel coupons using chlorine dioxide gas. Applied Environmental Microbiology, 2015,(1):116-23.
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Erin DiCaprio, Anastasia Purgianto, Yuanmei Ma, John Hughes, Xiangjun Dai, and Jianrong Li. Attachment and localization of human norovirus and animal caliciviruses in fresh produce. International Journal of Food Microbiology, 2015, 211:101-108.
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Elbashir Araud, Erin DiCaprio, Zhihong Yang, Xinhui Li, Fangfei Lou, John H. Hughes, Haiqiang Chen, and Jianrong Li. High-pressure inactivation of rotaviruses: role of treatment temperature and strain diversity in virus inactivation. Applied Environmental Microbiology 2015, 81(19):6669-6678.
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Ashley Predmore, Gabriel Sanglay, Erin DiCaprio, Jianrong Li, Robert Uribe, Ken Lee. Electron beam inactivation of Tulane virus on fresh produce, and mechanism of inactivation of human norovirus surrogates by electron beam irradiation. International Journal of Food Microbiology. 2015, 198:28-36.
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Erin DiCaprio, Anastasia Purgianto, Jianrong Li. The effect of abiotic and biotic stress on the internalization and dissemination of human norovirus surrogates in growing romaine lettuce. Applied and Environmental Microbiology 2015, 81(14):4791-800.
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Fangfei Lou, Hudaa Neetoo, Haiqiang Chen, Jianrong Li. High hydrostatic pressure processing: a promising nonthermal technology to inactivate viruses in high-risk foods. Annual Review of Food Science and Technology, 2015, 6:389-409.
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Erin DiCaprio E, Douglas Culbertson, Jianrong Li. Evidence of the internalization of animal caliciviruses via the root of growing strawberry plants and dissemination to the fruit. Applied Environmental Microbiology. 2015, 81(8):2727-34.
  • Type: Journal Articles Status: Published Year Published: 2012 Citation: Lizanel Feliciano, Jianrong Li, Jaesung Lee, Melvin Pascall. "Efficacies of sodium hypochlorite and quaternary ammonium sanitizers for reduction of norovirus and selected bacteria during ware-washing operations". PLoS One. 2012. 7(12), e50273.
  • Type: Books Status: Awaiting Publication Year Published: 2016 Citation: Erin Dicaprio, Fangfei Lou, Jianrong Li. Book chapter Novel strategies to control human norovirus. Viral Foodborne Pathogens, Editor: Peter White; CRC Press, 2016. In Press.
  • Type: Theses/Dissertations Status: Published Year Published: 2015 Citation: Elbashir Araud. Identification of Effective and Practical Thermal and Non-thermal Processing Technologies to Inactivate Major Foodborne Viruses in Oysters. 2015. Ph.D. thesis. Advisor: Jianrong Li. The Ohio State University.
  • Type: Theses/Dissertations Status: Published Year Published: 2012 Citation: Erin DiCaprio. Attachment, Internalization, and Dissemination of Human Norovirus and Animal Caliciviruses in Fresh Produce. 2012. MS thesis. Advisor: Jianrong Li. The Ohio State University.
  • Type: Theses/Dissertations Status: Published Year Published: 2015 Citation: Erin DiCaprio. Internalization and Dissemination of Human Norovirus and Animal Caliciviruses in Fresh Produce and Non-thermal Processes to Inactivate Human Norovirus. 2015. Ph.D. thesis. Advisor: Jianrong Li, The Ohio State University.
  • Type: Journal Articles Status: Published Year Published: 2011 Citation: Ashley Predmore. Enhanced Sanitization of a Human Norovirus Surrogate in Fresh Vegetables and Fruits by a Combination of Surfactants and Sanitizers. 2011. MS thesis. Advisor: Jianrong Li. The Ohio State University.
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Ashley Predmore, Gabriel Sanglay G, Jianrong Li, Ken Lee. Control of human norovirus surrogates in fresh foods by gaseous ozone and a proposed mechanism of inactivation. Food Microbiology 2015, 50:118-25.
  • Type: Theses/Dissertations Status: Published Year Published: 2015 Citation: Ashley Predmore. Various Non-Thermal Technologies and Their Effectiveness against Human Norovirus Surrogates. 2015. Ph.D. thesis. Advisor: Ken Lee. The Ohio State University.
  • Type: Journal Articles Status: Published Year Published: 2011 Citation: Fangfei Lou. Inactivation of Selected Non-enveloped and Enveloped Viruses by High Pressure Processing: Effectiveness, Mechanism, and Potential Applications. 2011. MS thesis. Advisor: Jianrong Li. The Ohio State University.
  • Type: Journal Articles Status: Published Year Published: 2014 Citation: Fangfei Lou. Survival of Nonculturable Human Noroviruses during High Pressure Processing. 2014. Ph.D. thesis. Advisor:Jianrong Li. The Ohio State University.
  • Type: Journal Articles Status: Published Year Published: 2012 Citation: Gabriel Sanglay. Inactivation and Mechanism of Electron Beam Irradiation and Sodium Hypochlorite Sanitizers against a Human Norovirus Surrogate. 2012. Ph.D. thesis. Advisor: Ken Lee. The Ohio State University.
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Moore MD, Goulter RM, Jaykus LA. Human norovirus as a foodborne pathogen: challenges and developments. Annu Rev Food Sci Technol. 2015;6:411-33.
  • Type: Journal Articles Status: Published Year Published: 2013 Citation: Tung G, Macinga D, Arbogast J, Jaykus LA. Efficacy of commonly used disinfectants for inactivation of human noroviruses and their surrogates. J Food Prot. 2013 Jul;76(7):1210-7.


Progress 09/01/12 to 08/31/13

Outputs
Target Audience: The goals of this proposal are to understand the attachment, internalization, and survival of foodborne viruses in vegetables and fruits and to develop novel sanitization and process technologies to inactivate the viruses. Our target audiences are (1) College graduate students and undergraduate students, food safety experts; (2) small and medium sized farmers since they are thought less likely to follow the most rigorous food safety protocols; (3) grower-packers and fresh produce processors since the cleaning, washing, cutting, and packaging of produce usually occurs in these plants; and (4) County Food Safety Extension Agents. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? This project has trained 10 graduate students and 15 undergraduates in food safety, microbiology and engineering. We have offered 2 courses for undergraduate and graduate students. The research findings have been incorporated into a number of courses including food safety and public health, food microbiology, food engineering, water contamination, and environmental health sciences. We have organized 14 training programs. Participants come from small and medium sized farmers, grower-packers and fresh produce processors, and county Food Safety Extension Agents. How have the results been disseminated to communities of interest? Viruses cause more than 67% of foodborne illnesses in the United States. Among those commonly known are human norovirus (NoV) and hepatitis A virus (HAV). It is estimated that more than 90% of outbreaks of acute nonbacterial gastroenteritis are caused by noroviruses. Also, more than 50% of all food-related gastroenteritis outbreaks are due to noroviruses. Fresh produce is one of the major high risk foods for virus contamination. To date, there is no effective method to eliminate the viruses from fresh produce. The goals of this proposal are to understand the attachment, internalization, and survival of foodborne viruses in vegetables and fruits and to develop novel sanitization and process technologies to inactivate the viruses in fresh produce. We experimentally demonstrated that fresh produce can be contaminated in both pre-harvest (via contaminated irrigation water and soil) and post-harvest (such as hand transfer, surface contact, and during processing). We found that NoV and HAV are internalized via the root and leaf, and disseminated to other portion of the plants. Using the novel in situ localization assay, we found that viruses were localized in the plant tissues (such as stomata). We found that commonly used sanitizers (such as chlorine solution) are not effective in removing viruses from fresh produce. We developed a novel strategy to enhance (100 times) the efficiency of viral removal from fresh produce by combination of a surfactant (such as SDS and polysorbates) with a commonly used sanitizer (such as chlorine solution). Implementation of this novel sanitization strategy would be a feasible approach for efficient reduction of the virus load in fresh produce. We found that high pressure processing (HPP) effectively inactivated major foodborne viruses (such as NoV, HAV, and rotavirus) in cell culture medium and fresh produce (such as lettuce, strawberries, raspberries, and blackberries) with a minimal impact on food quality. Therefore, HPP is a novel intervention for processing fruits intended for frozen storage and related products such as purees, sauces, and juices. We found that gaseous ozone can effectively inactivate foodborne viruses in cell culture medium, surface of equipment and fresh produce. Therefore, gaseous ozone can be used as a novel sanitizer to reduce virus contamination in the fresh produce prior to cooling-vacuum procedure. We also found that food irradiation (such as gamma irradiation and e-beam) has limited efficiency in inactivating foodborne viruses at the FDA approved dose for fresh produce. We have integrated these findings and technologies to our extension and outreach programs. These extension activities filled a critical gap in enhancing producer, processor, food handler understanding of foodborne viruses and those practices proven to minimize viruses in fresh produce. In addition, this project has trained 10 graduate students and more than 15 undergraduates in food safety, microbiology and engineering. These integrated research, extension, and education program improved food safety and public health in the United States. What do you plan to do during the next reporting period to accomplish the goals? We will continue to (1) determine mechanism by which plant stress and environmental factors affect the internalization of foodborne viruses in vegetables and fruits; (2) determine the mechanism of virus contamination in fresh produce; (3) to determine the effectiveness of different sanitizers (ozone and SDS) on removing enteric viruses from vegetables and fruits; (4) to determine the efficiency of high pressure processing and E-Beam on inactivating viruses in vegetables and fruits; (5) organize the extension and outreach programs in multiple states; and (6) to train and educate the graduate students and undergraduate students.

Impacts
What was accomplished under these goals? Fresh produce is a high risk food for enteric foodborne virus contamination. The overall goal of this project is to use an integrated approach to prevent and minimize the foodborne enteric viruses in vegetables and fruits. Objective 1 is to determine whether human norovirus (NoV) and hepatitis A virus (HAV) are internalized via the root and/or the surface of vegetables and fruits. We found that human NoV, animal caliciviruses (such as Tulane virus [TV] and murine norovirus [MNV-1]), and HAV attached tightly to the roots, became internalized via roots, and efficiently disseminated to the shoots and leaves of the lettuce. In Objective 2: we found that fresh produce was easily contaminated by human NoV and HAV via a number of routes such as transfer from hands, contact surfaces, and packaging materials. In Objective 3, we determined the effectiveness of different sanitizers on removing enteric viruses from vegetables and fruits. We found that sodium dodecyl sulfate (SDS), Nonidet P-40 (NP-40), Triton X-100, and polysorbates, significantly enhanced the removal of enteric foodborne viruses from fresh fruits and vegetables. We found that more than 3 logs virus reduction was observed in fresh produce after sanitization with a solution containing a combination of 50 ppm of each surfactant and 200 ppm of chlorine. In addition, other sanitizers such as ozone and chlorine dioxide also effectively inactivate the viruses on the surface of fresh produce. These novel strategies may be practical for removing surface viruses and thus enhance food safety and public health. In Objective 4, we determined the efficiency of non-thermal processing technologies (E-beam and high pressure processing) on inactivating NoV and HAV on the surface or internalized in vegetables and fruits. We found that high pressure processing effectively inactivated major foodborne viruses including human NoV, surrogates (MNV-1 and TV), and HAV. It is a feasible processing technology to inactivate the viruses in fresh produce related products such as puree and juice. In addition, we found that E-beam has limited efficacy in inactivating viruses from fresh produce. The Objective 5 is the extension and outreach. We have delivered and disseminated current knowledge and preventive practices to stakeholders and incorporated major research findings to target audiences such as grower and farmers. The Objective 6 is education component. We have developed “Food Safety and Public Health” and “Food Virology” courses. The research findings from this project has been integrated into a number of other courses including “Food Engineering”, “Current Topics in Environmental Health Sciences”, and “Water Contamination”. We have published these results in high-impact journals including Applied and Environmental Microbiology, Food Microbiology, and PLOS one. We have presented and disseminated these findings in Institute of Food Technologists (IFT) and International Association for Food Protection (IAFP) meetings. We have also integrated these findings into extension and outreach programs including Center for Food Safety conference, and Advanced CIP Cleaning and Sanitation program.

Publications

  • Type: Journal Articles Status: Published Year Published: 2014 Citation: Ravaliya K, Gentry-Shields J, Garcia S, Heredia N, Fabiszewski de Aceituno A, Bartz FE, Leon JS, Jaykus LA. Use of Bacteroidales microbial source tracking to monitor fecal contamination in fresh produce production. Appl Environ Microbiol. 2014, 80(2):612-7.
  • Type: Journal Articles Status: Published Year Published: 2013 Citation: Tung G, Macinga D, Arbogast J, Jaykus LA. Efficacy of commonly used disinfectants for inactivation of human noroviruses and their surrogates. J Food Prot. 2013, 76(7):1210-7.
  • Type: Journal Articles Status: Submitted Year Published: 2014 Citation: Huang, R., Li, x., Huang, Y. and Chen H. 2014. Strategies to enhance high pressure inactivation of murine norovirus in strawberry puree and on strawberries. Int. J. Food Microbiol. Submitted.
  • Type: Journal Articles Status: Published Year Published: 2013 Citation: Erin Dicaprio, Yuanmei Ma, John Hughes, Jianrong Li. Epidemiology, prevention, and control of the number one foodborne illness: human norovirus. Infectious Diseases Clinics of North America. 2013, 27(3):651-74.
  • Type: Book Chapters Status: Awaiting Publication Year Published: 2014 Citation: Erin Dicaprio, Fangfei Lou, Jianrong Li. Book chapter Novel strategies to control human norovirus. Viral Foodborne Pathogens, Editor: Peter White; CRC Press, 2014.
  • Type: Journal Articles Status: Published Year Published: 2013 Citation: Tian P, Yang D, Quigley C, Chou M, Jiang X. Inactivation of the Tulane virus, a novel surrogate for the human norovirus. J Food Prot. 2013;76(4):712-8.


Progress 09/01/11 to 08/31/12

Outputs
OUTPUTS: Fresh produce is a major vehicle for the transmission of human norovirus (NoV) because it is easily contaminated during both pre- and postharvest stages. The overall goal of this project is to determine the mechanism of viral contamination in fresh produce and to develop novel strategies to control foodborne viruses in fresh produce. (1) Internalization and dissemination of human norovirus and animal caliciviruses in hydroponically grown romaine lettuce. The roots of romaine lettuce growing in hydroponic feed water were inoculated with a human NoV or animal caliciviruses (Tulane virus [TV] and murine norovirus [MNV-1]), and plants were allowed to grow for 2 weeks. It was found that human NoV and animal caliciviruses attached tightly to the roots, became internalized via roots, and efficiently disseminated to the shoots and leaves of the lettuce. (2) High pressure (HPP) inactivation of human NoV, it surrogates, and other enteric foodborne viruses. We have systematically investigated the effectiveness of HPP on inactivating enteric foodborne viruses in aqueous medium and fresh produce. We demonstrated that HPP treatment at 400 MPa for 2 min is capable of inactivating most viruses including MNV-1, TV, hepatitis A virus, and rotavirus. More than a 5-log virus reduction was achieved in all tested fresh produce (lettuce, cabbage, strawberry, and blueberry) under these conditions. However, pressure, pH, temperature, and salts conditions affect the effectiveness of the viral inactivation. In addition, food matrix can provide protective effects for virus inactivation. Using human NoV virus-like particles (VLPs) as models, we also demonstrated that HPP disrupted the structural and functional integrity of viral capsid and disrupted the binding of VLPs to histo-blood group antigen (HBGA) receptors. (3) Novel interventions to remove viruses from fresh vegetables, fruits, tableware and food preparation utensils. We found that a panel of surfactants, including sodium dodecyl sulfate (SDS), Nonidet P-40 (NP-40), Triton X-100, and polysorbates, significantly enhanced the removal of enteric foodborne viruses from fresh fruits and vegetables. Moreover, a reduction of approximately 3 logs was observed in all the tested fresh produce after sanitization with a solution containing a combination of 50 ppm of each surfactant and 200 ppm of chlorine. This novel strategy (combination of surfactants and sanitizers) may be practical for removing surface viruses and thus enhance food safety and public health. (4) Education and extension. We have developed two courses addressing foodborne viruses including "Food Safety and Public Health" and "Advanced Food Microbiology-Food Virology". We have published these results in high-impact journals including Applied and Environmental Microbiology, and PLOS one. We have presented and disseminated these findings in Institute of Food Technologists (IFT) and International Association for Food Protection (IAFP) meetings. We have also integrated these findings into extension and outreach programs including Center for Food Safety conference, and Advanced CIP Cleaning and Sanitation program. PARTICIPANTS: Jianrong Li (The Ohio State University), Lee-ann Jaykus (North Carolina State University), Ken Lee (The Ohio State University), Doug Doohan (The Ohio State University), Xi Jiang (University Of Cincinnati), Haiqiang Chen (University of Delaware), Uribe, Roberto (Kent State University). TARGET AUDIENCES: Professionals in food safety, food microbiology, food virology, farmers, growers, fresh produce processors, county food safety extension agents. PROJECT MODIFICATIONS: Not relevant to this project.

Impacts
Foodborne illness can be caused by viruses, bacteria, fungi, parasites, or prions, but viruses are the major causative agent of foodborne gastroenteritis, accounting for more than 67% of foodborne illnesses worldwide. Commonly known foodborne viruses are human norovirus, hepatitis A virus, and rotavirus. CDC estimated that approximately 21 million people suffer from norovirus-induced gastroenteritis each year in the United States. It is also estimated that more than 90% of outbreaks of acute nonbacterial gastroenteritis are caused by noroviruses. Disease surveillance also showed fruits and vegetables are major vehicles for transmission of food-borne enteric viruses since they are easily contaminated at pre- and postharvest stages and they undergo little or no processing. Currently, there is no effective method to eliminate the viruses from fresh produce. The goals of this project are to understand the attachment, internalization, and survival of foodborne viruses in vegetables and fruits; to develop novel sanitization and process technologies to inactivate the viruses; and to prevent and minimize virus contamination in fresh produce via extension, outreach and education programs. Unfortunately, commonly used sanitizers are not effective in removing viruses from fresh produce. We developed a novel strategy to enhance (100 times) the efficiency of viral removal from fresh produce by combination of a surfactant (such as SDS and polysorbates) with a commonly used sanitizer (such as chlorine solution). Implementation of this novel sanitization strategy would be a feasible approach for efficient reduction of the virus load in fresh produce. We also experimentally demonstrated that human norovirus and its surrogates (murine norovirus and Tulane virus) attached tightly to the fresh produce and became efficiently internalized and disseminated to other portion of the plants. This suggests that viral internalization may be an important route for contamination of fresh produce. We also investigated a number of non-thermal processing technologies in inactivating foodborne viruses in foods. By optimizing processing parameters, we found that high pressure processing (HPP) is capable of inactivating most food- and water-borne viruses including human norovirus, surrogates (murine norovirus and Tulane virus), hepatitis A virus, and rotavirus, without having significant impacts on food quality. Thus, HPP may be a novel intervention to eliminate virus contamination in fruits intended for frozen storage and related products such as purees, sauces, and juices. In contrast, food irradiation (such as gamma irradiation and e-beam) has limited efficiency in inactivating foodborne viruses. To enhance our capability to compact foodborne viruses, we have developed two courses "Food Safety and Public Health" and "Advanced Food Microbiology-Food Virology". In conclusion, we developed a panel of novel interventions (sanitizers and non-thermal processing technologies) that can enhance removal and inactivation of virus from fresh produce. Implementation of these novel strategies and interventions in fresh produce industry will improve the safety of vegetables and fruits.

Publications

  • [1] Erin DiCaprio, Yuanmei Ma, John Hughes, Jianrong Li*. Internalization and dissemination of human norovirus and animal caliciviruses in hydroponically grown Romaine lettuce. Applied and Environmental Microbiology. 2012. 78(17):6143-6152
  • [2] Lizanel Feliciano, Jianrong Li*, Melvin Pascall. Efficacies of sodium hypochlorite and quaternary ammonium sanitizers for reduction of norovirus and selected bacteria during ware-washing operations. PlOS One. 2012, ;7(12):e50273.
  • [3] Fangfei Lou, Pengwei Huang, Hudaa Neetoo, Joshua Gurtler, Brendan Niemira, Haiqiang Chen, Xi Jiang, Jianrong Li*, "High pressure inactivation of human norovirus virus-like particles: evidence that the capsid of human norovirus is highly pressure resistant". .Applied and Environmental Microbiology. 2012. 78(15):5320-5327.
  • [4] Jianrong Li*, Ashley Predmore, Erin Divers, Fangfei Lou. 2012. New interventions against human norovirus: progress, opportunities, and challenges. Annual Review of Food Science and Technology. 2012. 3: 331-352.


Progress 09/01/10 to 08/31/11

Outputs
OUTPUTS: We have made significant progress on this project. (1) Enhanced removal of a human norovirus surrogate from fresh vegetables and fruits by a combination of surfactants and sanitizers. We found that a panel of surfactants, including sodium dodecyl sulfate (SDS), Nonidet P-40 (NP-40), Triton X-100, and polysorbates, significantly enhanced the removal of murine norovirus (MNV-1) from fresh fruits and vegetables. While chlorine solution (200 ppm) gave less than 1.2-log virus reductions in tested fresh produce, a solution containing 50 ppm of surfactant was able to achieve a 3-log virus reduction in strawberries and an approximately 2-log virus reduction in lettuce, cabbage, and raspberries. Moreover, a reduction of approximately 3 logs was observed in all the tested fresh produce after sanitization with a solution containing a combination of 50 ppm of each surfactant and 200 ppm of chlorine. (2) Inactivation of a human norovirus surrogate in fresh produce by high-pressure processing (HPP). We have systematically investigated the effectiveness of HPP on inactivating murine norovirus (MNV-1) in aqueous medium and fresh produce. We demonstrated that more than a 5-log virus reduction was achieved in all tested fresh produce (lettuce, cabbage, strawberry, and blueberry) when it was pressurized at 400 MPa for 2 min at 4 degrees. We found that pressure, pH, temperature, and food matrix affected the virus survival in foods. MNV-1 was more effectively inactivated at 4 degrees than at 20 degrees in both medium and fresh produce. MNV-1 was also more sensitive to HPP at neutral pH than at acidic pH. We further demonstrated that disruption of viral capsid structure, but not degradation of viral genomic RNA, is the primary mechanism of virus inactivation by HPP. (3) Inactivation of a human norovirus surrogate (MNV-1) by gamma irradiation. We demonstrated that MNV-1 was resistant to gamma irradiation. Only a 1.7- to 2.4-log virus reduction in fresh produce at the dose of 5.6 kGy was observed. We further demonstrated that gamma irradiation disrupted virion structure and degraded viral proteins and genomic RNA, which resulted in virus inactivation. Overall, our results suggest that viruses are much more resistant to irradiation than bacterial pathogens. (4) Electron-beam inactivation of a norovirus surrogate in fresh produce and model systems. We found that e-beam at 2 kGy provided less than a 1-log reduction of murine norovirus in PBS and DMEM. Irradiation of inoculated cabbage showed up to a 1-log reduction at 4 kGy, and less than a 3-log reduction at 12 kGy. On strawberries, less than a 1-log reduction occurred at doses up to 6 kGy, with a maximum reduction of 2.21 log at 12 kGy. Overall, MNV-1 is highly resistant to e-beam. Ongoing experiments are aimed to determine the attachment and internalization of foodborne viruses in vegetables and fruits; to determine the efficiency of non-thermal processing technologies on virus inactivation in vegetables and fruits; and to integrate research findings to extension, outreach, and education programs. PARTICIPANTS: Jianrong Li (The Ohio State University), Lee-ann Jaykus (North Carolina State University), Ken Lee (The Ohio State University), Doug Doohan (The Ohio State University), Xi Jiang (University Of Cincinnati), Haiqiang Chen (University of Delaware), Uribe, Roberto (Kent State University) TARGET AUDIENCES: Professionals in food safety, food microbiology, food virology, farmers, growers, fresh produce processors, county food safety extension agents PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
Viruses cause more than 67% of foodborne illnesses worldwide, and among the most common are human norovirus and hepatitis A virus. Human norovirus is the major foodborne enteric virus that causes gastroenteritis in humans. It is estimated that more than 90% of outbreaks of acute nonbacterial gastroenteritis are caused by noroviruses. Disease surveillance also showed fruits and vegetables are major vehicles for transmission of food-borne enteric viruses since they are easily contaminated at pre- and postharvest stages and they undergo little or no processing. Currently, there is no effective method to eliminate the viruses from fresh produce. The goals of this proposal are to understand the attachment, internalization, and survival of foodborne viruses in vegetables and fruits; to develop novel sanitization and process technologies to inactivate the viruses; and to prevent and minimize virus contamination in fresh produce via extension, outreach and education programs. Since we started this project, we have made significant progress. First, we found that the combination of a surfactant (such as SDS and polysorbates) with a commonly used sanitizer (such as chlorine solution) enhanced the efficiency in removing viruses from fresh produce by approximately 100 times. Since SDS is an FDA-approved food additive and polysorbates are recognized by the FDA as GRAS (generally recognized as safe) products, implementation of this novel sanitization strategy would be a feasible approach for efficient reduction of the virus load in fresh produce. Second, we found that high pressure processing (HPP) effectively inactivated a human norovirus surrogate in fresh produce with a minimal impact on food quality and thus can provide a novel intervention for processing fruits intended for frozen storage and related products such as purees, sauces, and juices. Third, we found that food irradiation (such as gamma irradiation and e-beam) has limited efficiency in inactivating foodborne viruses. Currently, the FDA has approved doses of up to 4.0 kGy to control food-borne pathogens in fresh iceberg lettuce and spinach. However, less than 1.5 log virus reduction in fresh produce was observed at 4.0 kGy of irradiation. Fourth, we have revealed the mechanism of virus inactivation by non-thermal processing technologies including high pressure processing and irradiation. Thus, we developed novel sanitizers that can enhance removal of virus from fresh produce and identified non-thermal processing technologies that can effectively inactivate viruses in fresh produce. Implementation of these novel strategies and interventions in fresh produce industry will improve the safety of vegetables and fruits.

Publications

  • [3] Ashley Predmore, Jianrong Li. Enhanced Sanitization of a Human Norovirus Surrogate in Fresh Vegetables and Fruits by a Combination of Surfactants and Sanitizers. Applied and Environmental Microbiology, 2011, 77(14):4829-4838.
  • [4] Gabriel Sanglay, Jianrong Li, Roberto Uribe, Ken Lee. Electron beam inactivation of a norovirus surrogate in fresh produce and model system. Journal of Food Protection, 2011, 74(7):1155-1160.
  • [5] Jianrong Li, Ashley Predmore, Erin Divers, Fangfei Lou. New interventions against human norovirus: progress, opportunities, and challenges. Annual Review of Food Science and Technology, 2011, in press. Invited review.
  • [2] Kurtis Feng, Erin Divers, Yuanmei Ma, Jianrong Li. Inactivation of human norovirus surrogate, human norovirus virus-like particle, and vesicular stomatitis virus by gamma irradiation. Applied and Environmental Microbiology, 2011, 77(10):3507-3517.
  • [1] Fangfei Lou, Hudaa Needoo, Haiqiang Chen, Jianrong Li. Inactivation of human norovirus surrogate by high pressure processing: effectiveness, mechanism and potential application in fresh produce industry. Applied and Environmental Microbiology, 2011, 77(5):1862-1871.