Since the COVID-19 crisis emerged in the U.S., researchers and faculty at the University of Georgia’s College of Agricultural and Environmental Sciences have worked quickly to contribute to the knowledge base around the novel coronavirus, launching and participating in a number of studies aimed at prevention and control of its spread.
An assistant professor of food virology at the UGA Center for Food Safety (CFS) in Griffin, Malak Esseili has focused on studying the microbial ecology of human viral pathogens such as human noroviruses, and now her work includes the emerging viral pathogen SARS-CoV-2, the virus that causes COVID-19.
In March, just before the university shut down in response to the COVID-19 pandemic, members of the CFS met with the center’s board of directors — comprised of food industry leaders and representatives from the Centers for Disease Control and Prevention.
“We were just hearing about the outbreaks in the U.S., we didn’t know what this novel coronavirus was and everyone was curious here. I gave a talk at that meeting because I had worked on coronaviruses before,” said Esseili, who joined UGA in March 2019 after eight years with the Food Animal Health Research Program at The Ohio State University (OSU), where she studied under faculty with decades of research on coronaviruses and other zoonotic viruses.
“They asked if it was culturable, and I said yes, but it is a Biosafety Level 3 (BSL3) pathogen and we did not have the facilities to handle it safely,” she said.
That question set into motion an ambitious plan to rebuild a former BSL3 lab at CFS that had been decommissioned more than a decade ago and since transformed into a normal BSL2 lab.
At Esseili’s suggestion, CFS Director Francisco Diez spearheaded the effort to rebuild the lab, working with UGA’s Institutional Biosafety Committee (IBC) to plan and execute the design and buildout for the lab.
Upgrades started in April, the lab was certified as a BSL3 facility in September and completed with most of the equipment installed in October. Esseili’s first research project in the lab involves verifying the efficacy of some of the sanitizers and disinfectants on a list approved for emergency use by the Environmental Protection Agency.
“While these sanitizers and disinfectants have been approved for emergency use, only a few of them have been verified on the COVID-19 virus. Many things need to be tested, in terms of what dilutions should be used, the contact time needed to kill the virus and other variables unique to this virus, as well as investigating alternative novel sanitizers and anti-virals,” Esseili said.
Human and animal coronaviruses are all shaped the same, she said, but they can behave differently within a particular host and in terms of environmental stability and inactivation.
“These viruses are not wimpy and can survive for days to weeks in the environment, depending on the particular viral strain, temperature, humidity and what they land on,” she said.
The next priority will be to determine whether the virus can survive on food, as there have been reports of the virus being found on packaging and in frozen foods in China.
“There is a great deal of consumer anxiety and industry concern. This research really needs to be done precisely, not just to answer the question of whether it can survive on food, but also what we can do about it,” added Esseili, who has extensive experience working on foodborne pathogens in produce and frozen foods. “This virus is different than traditionally known foodborne viruses such as norovirus or Hepatitis A virus, so it is important to do research on this specific virus. Now we have the lab facilities to do that and to help the consumers and the food industry and contribute to controlling the pandemic in Georgia and beyond.”
COVID-19 has caused significant impacts on the food industry, which has witnessed closures due to COVID-19 illnesses in food workers.
“These industries are not only vital to the local economy in Georgia, but they also contribute to food security, which is crucial to maintain a healthy population,” she said.
Understanding the science
As COVID-19 began to spread throughout the U.S. earlier this year, a team including Govind Kumar, an assistant professor in the Department of Food Science and Technology and a faculty member in the UGA Center for Food Safety; Laurel Dunn and Abhinav Mishra, assistant professors in the Department of Food Science and Technology; and Center for Food Safety Director Francisco Diez collaborated to determine ways they could contribute to the knowledge base for members of the food industry regarding the novel coronavirus.
Govind Kumar and his fellow researchers looked at studies on a range of biocides effective in eliminating or reducing the presence of coronaviruses from surfaces that are likely to carry infection, such as clothes, utensils and furniture, as well as skin, mucous membranes, air and food contact materials.
“Meat manufacturing plants began to shut down because so many people in these industries were getting sick. We are not virologists, but this is a medical problem that definitely affected the food chain,” Kumar said.
With information and scientific studies about the virus being released at a rapid rate, the CAES researchers decided to examine relevant studies to identify and share practicable information for use in the food industry. The research team looked at studies on a range of biocides effective in eliminating or reducing the presence of coronaviruses from surfaces that are likely to carry infection, such as clothes, utensils and furniture, as well as skin, mucous membranes, air and food contact materials.
After reviewing and synthesizing the information from more than 100 sources, the online journal Frontiers in Microbiology published the researchers’ findings in “Biocides and Novel Antimicrobial Agents for the Mitigation of Coronaviruses” in late June.
“We wanted to go through the whole food supply chain — from processing to packaging to retail — to look at interventions to limit the spread of coronaviruses. This is not limited to handwashing, but looks at everything — how you can remove it from the air and from food contact surfaces. We asked a lot of tough questions and we feel we have answered those in this paper,” Kumar said.
The research team specifically focused on the effects of alcohols, povidone iodine, quaternary ammonium compounds, hydrogen peroxide, sodium hypochlorite (NaOCl), peroxyacetic acid (PAA), chlorine dioxide, ozone, ultraviolet light, metals and plant-based antimicrobials. The review highlights the differences in the resistance or susceptibility of different strains of coronaviruses, or similar viruses, to these antimicrobial agents. The team also worked with microbiologists Charles Gerba and Kelly Bright from the University of Arizona who are currently performing research on detecting the presence of SARS-CoV-2 in wastewater.
The review reinforced the effectiveness of certain antimicrobials — such as bleach and alcohol — on surfaces, while also addressing studies on agents that can be used to protect workers themselves.
“A lot of what I’ve gotten have been questions about what can be used on the skin. We got crazy questions like, ‘Can we spray our workers with chemicals?’ A lot of questions have been about what steps they can take in certain types of facilities. It is not necessarily about sanitizer selection, but what to do in general,” said Dunn, who does outreach and Extension work in on-farm and packinghouse microbial safety.
Handwashing and the use of sanitizers are commonly implemented practices in food production plants, however the team sought to address the spread of COVID-19 from asymptomatic workers, who often work in crowded conditions. To this end, they focused on a number of studies of two substances — povidone iodine and iota carrageenan — that were of particular interest in preventing person-to-person transmission of coronaviruses.
“Povidone iodine is very effective against coronaviruses and, in Europe and Asia, people use povidone iodine for oral rinses and nasal sprays. Because this is an airborne virus, the first place it goes is into the nose and it attaches to the cell receptors in the nose,” Kumar said.
A seaweed-based antimicrobial polymer, iota carrageenan is commonly used as a food thickener and, in a 2018 study, demonstrated the ability to inhibit coronaviruses and other respiratory viruses.
“When sprayed in the nose in nasal spray form, iota carrageenan can form a protective film over the nasal membranes and keep the virus from attaching,” Kumar said.
While not performing any direct research, Kumar and Dunn said the synthesis of information from a variety of studies — some from this year and others done over the past 20 years — can serve as a sort of “CliffsNotes” for industry members seeking the most relevant and useful information on preventing transmission of COVID-19.
“We wanted to get that information out for the industry to investigate further or do more research,” Kumar said.
The team’s full paper is available here.
Industry safeguards
Poultry researchers Harsha Thippareddi, John Bekkers Professor in Poultry Science at UGA, and Manpreet Singh, poultry science professor and interim head of the UGA Department of Food Science and Technology, are partnering with a team from Kansas State University to study how to effectively control the spread of SARS-CoV-2 in the nation’s meat and poultry processing facilities.
Thippareddi and Singh, who are co-directing the project with A. Sally Davis, an assistant professor of experimental pathology in the Kansas State College of Veterinary Medicine, provide extensive poultry experience, industry connections and backgrounds as food safety specialists to lead the grant’s industry outreach efforts.
A key objective of the project will be verifying the effectiveness of many of the approved cleaners and sanitizers for inactivating SARS-CoV-2 during plant processing and sanitation operations with the goal of protecting meat plant workers and their surrounding communities from the spread of COVID-19 through practical solutions. The research is funded by a $1 million grant from the U.S. Department of Agriculture.
Harsha Thippareddi, John Bekkers Professor in Poultry Science at UGA, will be part of a team verifying the effectiveness of many of the approved cleaners and sanitizers for inactivating SARS-CoV-2 during plant processing and sanitation operations.
“Because there have been a number of outbreaks among employees in meat processing plants, there is always a perception that food or meat can be contaminated as well,” said Thippareddi. Frozen chicken wings imported to China from Brazil in August tested positive for SARS-CoV-2, he said. “This is a potential issue and we need to know the answers to what the risks to humans are if the coronavirus is present in food, and will it survive in the food or will it be destroyed during cooking and other food processing operations?”
Using Kansas State’s Biosecurity Research Institute, a high-containment research facility, researchers will study various potential contamination methods for meat and poultry, how long the virus survives on meat products, how various storage and preparation methods influence the infectivity of the virus and what product-treatment methods can be used to mitigate the virus on food products.
“Nationally and internationally, many facilities that produce meat and poultry products have been temporarily closed because of COVID-19 outbreaks,” said Davis, Kansas State’s project director of the grant. “This has put a major strain on food production, limiting the amount of meat and poultry on grocery store shelves and disrupting food and feed supply chains across the globe.”
While animals, such as cattle, swine and chickens, do not carry the virus, infections with SARS-CoV-2 are primarily thought to occur by exposure to microdroplets in the air generated by infected workers.
“The ultimate goal would be for us to better understand how the SARS-CoV-2 virus — if at all — can be transmitted through meat and poultry and through contact surfaces in poultry plants,” Singh said. Thippareddi added that “people working in meat processing plants may have the illness and, if it is aerosolizing, the virus can get onto the meat. If it is on the meat, it can get to people. All the poultry processing plants are taking preventive measures to stop the spread of the virus, because if you can prevent people from getting the virus and keep the virus from being aerosolized, you can prevent it getting onto the food.”
The team will evaluate potential sources of exposure and determine the amount and the longevity of infectious virus that is present during and after meat processing and packaging activities. Researchers seek to identify, develop, validate and deliver practical cleaning and disinfection strategies, in addition to developing mathematical models to predict and reduce the risk of SARS-CoV-2 exposure in meat and poultry processing facilities.
Information on all of the research being performed around COVID-19 at UGA is available here.
