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E. coliO157:H7 and its shigatoxin-producing cousins are currently a major focus of public health programs, research programs and beef industry efforts, and this will be a primary regulatory and research focus for the next several years, says Randall Phebus, Ph.D., Professor of Food Safety & Defense at KSU. He is also a scientific principal investigator (PI) at the BRI.
BRI researchers have been active in understanding the risks this group of pathogens poses to the beef industry. “We have been developing detection methodologies targeting this broader group of STEC [Shiga Toxin-Producing Escherichia coli], and my colleague Dr. T.G. Nagaraja’s research group has successfully developed a multi-plex polymerase chain reaction[PCR] assay that detects the seven primary STEC simultaneously from environmental and bovine fecal samples.”
Research is further validating this assay for beef products and surveillance studies have been conducted to gauge the prevalence of these different STEC in production environments.
“I am working with Dr. Harshavardhan Thippareddi at the Univ. of Nebraska to model the growth and survival of non-O157:H7 STEC in beef products to generate quantitative predictive tools for regulatory and industry use,” Phebus says. “Dr. Thippareddi and I have worked for the past three years with Dr. John Luchansky at USDA’s Eastern Regional Research Center in Pennsylvania to quantify the risks associated with production and cooking of non-intact beef products relative to STEC [work conducted in his USDA ARS laboratory].”
BRI researchers are gearing up to conduct a very large inoculated study looking at the distribution tendencies ofE. coli O157:H7, assuming that some level of non-uniform contamination of boneless beef trimmings occur during grinding operations, plus they will evaluate various sampling and detection strategies at successive points in the ground beef system, he adds. “We will be looking at various contamination scenarios of 2,000-lb. combo units that are ground and packaged simulating commercial processes.”
As a principal investigator at the facility, Phebus brings in and executes defined research projects.
“We are now conducting sponsored research with select agents, which are pathogens or biological toxins that have been declared by the US government to pose severe threats to public health and safety, including plant and animal health,” Phebus says.
As a PI approved for possession and use of these agents, it is his responsibility to ensure that all rules are followed, a detailed agent inventory is maintained, BRI complies with university and federal biosecurity and training schedules, and that all activities involving the use of the select agent is done to minimize risks.
Phebus has been heavily involved in creating the vision of the BRI food processing suite, designing it for processing functionality as a research unit, equipping it with processing and laboratory equipment and validating it will function as required to allow the facility to conduct the best possible research in a safe manner. “Research projects within the BRI were initiated in 2008 in lab spaces that had been completed and certifi ed, and now we are moving larger food/meat-related projects into the food processing suite to initiate within the next couple of months,” he says.
To date, BRI’s research primarily has been focused on large animal health and disease issues and control of important crop diseases, such as porcine reproductive and respiratory syndrome (PRRS) and wheat blast. Most recently the BRI became home to the US Department of Homeland Security funded Center of Excellence for Emerging and Zoonotic Animal Diseases(CEEZAD). The US Dept. of Agriculture’s Arthropod-Borne Animal Diseases Research Unit (ARADRU) also recently located to Manhattan, Kan., and is conducting its biocontainment research activities within the BRI.
Since 2005, Dr. Richard Oberst and Phebus have been leading research sponsored by the US Army (Natick Soldier Systems Center) to validate various in-field, bioagent detection systems to ensure the safety of the military’s food supply.
“The goals of our research are to prove the capabilities of detection systems of interest to the military [i.e. detection limits and accuracy against defi ned targets, and impact of potential interfering sample components] when analyzing a diverse set of food types for numerous bioagents that might be present, either by intentional or natural contamination scenarios,” Phebus says. “Our research is now expanding to evaluate and quantify risks associated with defi ned commercial simulated food processing activities; focusing on understanding bioagent distribution, determining effective sampling strategies, modeling agent growth and/or survival, and ultimately controlling risks in various food commodities including meat and poultry products.”
The beauty of the Natick-funded research projects they also have direct application and benefi t to day-to-day food processing in the US and beyond, Phebus says.
“Often we are characterizing traditional foodborne pathogens utilizing standard sampling and testing methods, or employing common pathogen control strategies,” he adds. “With the large scale of research we can do, we can closely replicate commercial processing while under biocontainment thereby providing more realistic answers and predictive capabilities.”
With a research facility as large and complex as the BRI, building its external features was the easy part.
“To protect our lab workers and the external environment, the building must be equipped with sophisticated air- and waste-handling systems that are integrated across the entire facility, are proven and then re-proven to work in all kinds of artificial failure scenarios, and fi nally are certified by the Centers for Disease Control and Prevention and/or USDA to meet federal standards for biosafety level 3 and 3 Ag operations,” Phebus says. “We have been gaining these approvals for various research spaces within the facility for the past couple of years.”
In the BRI’s animal abattoir and food-processing suite, efforts were made to procure and install processing equipment meeting BSL-3 operation, cleaning and disinfection standards, then re-aligning building air, waste and personnel operation systems to accommodate running the equipment.
“When you are running a full-scale Chad carcass wash cabinet within a functioning biocontainment facility, you have to modify it to minimize aerosol sprays, capture and decontaminate steam vapors to prevent fouling of HEPA filters, and maintain directional airflow between two large processing rooms,” Phebus says. “We have approximately $30,000 invested merely in sanitary welding on the Chad cabinet to ensure our ability to effectively decontaminate it after pathogen-inoculated studies.”
Another unique piece of equipment custom-designed for BRI’s work on carcass antimicrobial intervention treatments is a 6’x6’x12’ sealed carcass inoculation cabinet that facilitates uniform application of microbial cultures to the whole carcass using electrostatic spray technology followed by intervention applications to validate their efficacy, he adds.
Future endeavors
Phebus and colleagues will continue to model the growth and/or survival of various STEC strains in beef and other food matrices to generate data to support predictive modeling tools.
After a couple more months of grinding equipment set-up and installation and project planning [experimental design finalization, discussions with beef processors, and securing university required biosafety approvals], the BRI will conduct the large beef trim grinding project. Two antimicrobial intervention technologies are scheduled for validation on raw beef carcasses and/or fabricated products this year. Phebus anticipates validation studies for other technologies shortly after.
“We will be working diligently to publish our fi ndings via peer-reviewed manuscripts, along with industry and consumer-based guidance through multiple channels,” Phebus says.
BRI colleagues plan to develop traditional and distance-oriented educational materials to improve awareness and effective control of STEC in food. “We plan to train students, producers, process line workers, managers, and regulators in the most effective sampling and detection strategies, effective use of processing technologies and procedures, and how to properly use risk management tools to minimize STEC risks,” he adds.
Other KSU programs will provide extensive support to these efforts.
“The Biosecurity Research Institute is a national treasure in terms of a research and education facility,” Phebus points out.
“It is a facility that we see as supporting government, academic and industry needs across the nation for decades to come,” he concludes.
