The GFSI (Global Food Safety Initiative) Global Food Safety Conference, a unique annual event bringing together over 1,000 leading food safety specialists from over 50 countries to advance food safety globally, recently met in Houston from Feb. 28 to March 3. A panel discussion about collaborative ways industry, academia and regulators address Listeria control turned to a discussion about whole genome sequencing technology and what it may mean for the future of food safety.
Robert Tauxe, Ph.D., director of the division of foodborne, waterborne and environmental diseases at the Centers for Disease Control and Prevention in Atlanta, said that in 2013 the agency started a pilot project with the CDC that used whole genome sequencing. He said the results showed there was more to be learned about Listeria and more to be found.
“We are finding and solving more outbreaks, but finding them when they are smaller,” he said during the conference session.
Tauxe went on to note the use of whole genome sequencing at the CDC will be expanded in 2018 to identify other pathogens, such as Salmonella, Campylobacter and E. coli. “Whole genome sequencing is a major step forward in outbreak detection and investigation,” he said.
The CDC’s use of the technology may put food and beverage manufacturers in a bind, because regulators will have access to a more powerful technology to detect and trace outbreaks. A question arose during the panel session regarding how food manufacturers may use the technology, but not face greater regulatory scrutiny based on the findings.
Mickey Parish, senior science adviser for the Food and Drug Administration’s Center for Food Safety and Applied Nutrition, said the agency would encourage industry to adopt whole genome sequencing for their own internal purposes.
“We recognize they may want to take baby steps by looking at spoilage organisms initially to become more comfortable with the technology,” he said. “From there move toward the pathogen area.
“We are using it for regulatory purposes. Therefore a prudent firm might decide that if FDA is using it in this way we need to use it to stay ahead.”
Matthew Stasiewicz, Ph.D., an assistant professor of food microbiology at the Univ. of Illinois, Urbana-Champaign, said his research which involved searching for and identifying the sources of pathogens in 30 delis across the country said whole genome sequencing may improve the identification of persistent Listeria monocytogenes in food environments.
Ongoing challenges
While the use of whole genome sequencing became a running theme throughout the conference session, speakers focused on the challenges faced by the food industry in reducing the incidence of the Listeria pathogen.
“There is no one in the food industry who is not concerned about being hit by this,” said Anthony Huggett, vice president and head of quality management for Nestle S.A., Vevey, Switzerland. “All food sectors are hit by this and an industry-wide response is necessary.”
Tauxe said approximately 800 cases of Listeriosis occur in the United States each year, that almost all who are infected are hospitalized and an estimated 16 percent die.
One industry group that has had success in controlling Listeria is processed meats manufacturers. John Butts, Ph.D., vice president of research for the processed meats manufacturer Land O’ Frost, Munster, Indiana, and president of Food Safety by Design, a consultancy, said processed meat companies have been measured for Listeria by the US Dept. of Agriculture’s Food Safety and Inspection Service for the past 25 years and, over time, the percent of positive results have declined.
“It’s this simple,” he said. “Eliminate the residents, control transfer of the organism and deploy process management techniques.”
Best practices, he said, have proven essential to Listeria control in the meat industry including having clean, dry floors that do not have cracks. Equipment should require one tool or no tools for disassembly to be cleaned. Cleaning-out-of-place should be used for small parts, equipment sub-assemblies, and hand tools. Heat intervention should be used on large equipment.
Donna Garren, Ph.D., senior vice president of regulatory and technical affairs for the American Frozen Food Institute, McLean, Virginia, emphasized that when the processed meat industry came together to work on the issue they saw the number of Listeria incidents decline.
