Although human noroviruses are the most common cause of foodborne disease, responsible for more than 5 million cases in the United States each year, they get much less attention for their links to foodborne illness outbreaks than Salmonella, Listeria, and E. coli.
Classic food microbiology has always been about bacteria, and understanding food viruses is a completely different beast. There just aren’t that many of us who are trained to understand them.
Lee-Ann Jaykus, PhD, North Carolina State University
That’s partly because they’re more challenging for the food safety field to understand, said Lee-Ann Jaykus, PhD, a professor in the department of food, bioprocessing and nutrition sciences at North Carolina State University in Raleigh. “Classic food microbiology has always been about bacteria, and understanding food viruses is a completely different beast,” she explained. “There just aren’t that many of us who are trained to understand them.”
That may be about to change. The science of noroviruses and foodborne illnesses will get a kick-start with a five-year, $25 million grant from the U.S. Department of Agriculture’s (USDA) National Institute of Food and Agriculture (NIFA)—the largest such grant the agency has given—which the school will use to strengthen food safety by studying human noroviruses across the food supply chain in an effort to design effective control measures and reduce the number of virus-caused foodborne illnesses.
Her group, called the USDA-NIFA Food Virology Collaborative, is a team of more than 30 collaborators from academia, industry, and government. The team will work to increase understanding of the viruses; educate producers, processors, and food handlers on safe handling and preparation of food; and develop control and management strategies to reduce food contamination before and after harvesting.
Key goals for the venture, Dr. Jaykus said, include developing better detection methods for clinical, environmental, and food samples, as well as better methods to discriminate among strains using tools like microarray approaches. “We also desperately need a human strain that we can culture, and we have a group working on that,” she said. “In the meantime, we also need better surrogates we can use in place of human norovirus. We also plan to develop risk models so that we can better understand transmission routes and approximate where and how people are getting sick, so that we can focus on the appropriate parts of the food chain.”
The three food groups most at risk for norovirus contamination are mollusks and shellfish, produce, and ready-to-eat foods contaminated by human food handlers. “That last category appears to be the most important,” Dr. Jaykus said.