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Improve Food Safety and Public Health: Safeguard Public Health and Reduce the Risk of Food-Borne Diseases

Introduction

The U.S. food supply is abundant, affordable, and conveniently delivered to the consumer. While generally  perceived as safe, public concern about food safety has increased. Each year in the U.S., an estimated 76 million persons contract foodborne illnesses with up to 5,000 deaths. A concern over foodborne illness and our food safety system prompted numerous activities including a report commissioned by Congress by the National Academy of Science and the President•s Food Safety Initiative in 1997. Since then, funding and various national initiatives involving collaborative activities have increased. CSREES and ARS have become leaders in food safety research, education, and extension by leveraging both their uniqueness and their ability to collaborate with each other.  ARS is the principal •in-house• research agency for USDA with > 2200 scientists in 100 locations. They maintain a close relationship with industry and other stakeholders so that when important methodologies are developed, the technologies can be transferred where needed in the field. CSREES is the primary extramural research agency with partnerships with the land grant university system so that CSREES may provide leadership in research, education, and extension programs. An integral part of CSREES is the National Research Initiative which is a competitive granting program. The following is a brief description of research, education, and extension efforts by both agencies to accomplish the three objectives under food safety.                                             

Objective 1:  Develop and demonstrate control procedures to eliminate hazards in animal foods from the farm and ranch to the grocery store

Through its food safety grant programs (the National Research Initiative, the National Integrated Food Safety Initiative, and the Initiative for the Future of Agriculture and Food Systems) as well as through special grants linked to other federal agencies, CSREES has developed important research programs. They include:

• An evaluation of the effect of water chlorination on the prevalence of E.coli0157:H7 and Campylobacter in feedlot cattle (Washington State University).
• An evaluation of the epidemiological aspects of combining E.coli0157:H7 control programs and feedlot performance (Kansas State University).
• An evaluation of a novel strategy to test and monitor beef feedlot food safety control points (University of Nebraska).
• Training for monitoring and decreasing the levels of Salmonella in swine through the use of antibiotic alternatives (Iowa State University).
• Development and evaluation of a farm-based strategy for the removal of campylobacters from poultry intestinal tracts prior to processing using bioactive nanoparticles  (Clemson University).
• Evaluation of strategies to corrupt the stress response systems of E. coliO157:H7, making the organism unable to survive in the bovine gastrointestinal tract (University of South Alabama).
• Characterization of different Listeria monocytogenes isolates of human, animal, and food origins by different methods in order to understand which specific subtypes cause human disease and how they differ from those subtypes not causing disease (Cornell University).
• The determination of risk factors associated with the contamination of fresh produce with human pathogenic organisms (The Tri-State Fruit & Vegetable Safety Consortium)

ARS scientists in various locations have developed these important technologies. They include:

• The development of a competitive exclusion culture under the trade name PREEMPT^TM  to control Salmonella on commercial broiler farms.
• The development of a competitive exclusion method using sodium chlorate as a feed additive for cattle, swine and poultry to selectively kill foodborne pathogens, e.g. Salmonella and E. coliO157 in the animal gut.
• The development of an electrostatic ionization space charger to reduce the number of airborne bacteria including  Salmonella enteritidis in the hatching and production environment.
• The development of a pre-harvest certification program for Trichinella.
• The evaluation of the practice of holding swine at the abattoir prior to slaughter as a source of Salmonella infection of market pigs.
• The development of imaging technology for the automated on-line inspection of poultry, beef and produce, to screen for wholesomeness, feces and ingesta.   

Objective 2:  Improve effectiveness of pathogen destruction technologies

Important research grants from CSREES include:

• The determination of the efficiency of certain gases on inactivation and inhibition of significant pathogenic and spoilage microorganisms in apples, strawberries, cantaloupe, lettuce, and mushrooms (Purdue University).
• The development and distribution of information and technical tools necessary for the U.S. meat and poultry industry to meet federal regulations that specify lethality performance standards for fully-cooked products (Michigan State University).
• The development and validation of models for the destruction of foodborne pathogens using high hydrostatic pressure processing methods. (University of Delaware).
• The development and validation of models for microbial inactivation during convection cooking of meats (Michigan State University).
• The verification of safe cooking endpoints for beef and pork using multiple antigen ELISA (Texas A&M University).
• The determination of the effectiveness of various combinations of heat and disinfectants/ detergents on inactivation of E. coliO157:H7 and Salmonella on alfalfa seeds (University of Georgia).

ARS scientists have played a significant role in the development of these intervention strategies:

• The development of red meat carcass antimicrobial spray treatments including: steam vacuums, high pressure water, and hot water; organic acids, plant-derived and synthetic chemicals.
• The development of materials that inhibit bacterial attachment such as polished stainless steel, metals, rubber and plastics to prevent pathogen transfer to food during processing.
• The development of a vacuum-steam-vacuum (VSV) process to reduce pathogens on the surfaces of foods such as: poultry, red meats, hot dogs, hams, fresh fruit and vegetables.
• The development and validation of processes for the destruction of foodborne pathogens using hydrodynamic (pressure-wave) and plasma-pulse spark technology.
• The development and validation of control procedures to prevent inconsistent cooked color-  cooked meat during cooking of hamburger meats.
• The validation of control procedures to remove pathogens from aquaculture products.
• The investigation of the use of bacteriophages applied to processed (meats) and non-processed packaged (fruit slices) food products to kill pathogens.
• The evaluation of the use of a variety of natural (bacteriocins such as nisin) and synthetic organic chemicals (acids such as benzoate) as additives to packaged food products.
• The evaluation of  the use of low temperature (cold shock) to sensitize pathogens to a subsequent thermal or UV processing step for fruit juice production/processing.
• The development and evaluation of a variety of chemical, physical, alternative packaging and storing intervention strategies for fresh fruits, vegetables and seed decontamination.
• The determination of whether the shelf life of ground meats could be extended by a combination of low-dose gamma irradiation, modified atmosphere and cold storage.
• The development and validation of time temperature models for FSIS and industry to inactivate pathogens in meats, and for the safe cooling rates of processed foods.
• The development and validation of microbial models for food processing systems to predict the behavior of bacterial pathogens. 

 Objective 3:  Reduce the threat of antibiotic resistance to public health

CSREES grants have produced significant findings in antimicrobial resistance. They include:

• The determination of the risk factors for Salmonella and Campylobacter infections and their drug resistance in dairy cattle (Michigan State University).
• The determination of the ecology of antimicrobial resistance of enteric Salmonella and E.coli in cattle (University of California).
• The evaluation of  the prevalence of foodborne antibiotic resistant and extraintestinal pathogenic E.coli in retail and pet foods (University of Minnesota).
• The description of the dynamics of antibiotic resistance in commensal E.coli isolated from calves, linkage of the patterns of resistance to management and environmental attributes, and development of educational modules (University of California).
• The determination of an association between the use of antimicrobial agents in swine production and the presence of antimicrobial resistance in human food-borne pathogens isolated from slaughter pigs (Michigan State University).
• The determination of the effect of antimicrobial treatment on the development of resistance in bacteria present in dairy cattle, and development of prudent antimicrobial-use guidelines specific for dairy cattle (Ohio State University).
• The determination of the progression of antimicrobial resistant phenotypes among enterohemorrhagic E. coli phenotypes of animal and human origin over the past thirty years (University of Maryland).

ARS is carrying out significant research programs on antimicrobial resistance at 3 locations, Athens, Ames and College Station. A coordinated research plan includes:

• The identification of the genetic mechanisms associated with the development and maintenance of antimicrobial resistance and development of  rapid tests to identify resistance genes.
• The determination of what effects the acquisition of resistance confers on the bacterium.
• Prospective ecological studies to better define the acquisition, transmission, and dissemination of antimicrobial resistance.
• A major role in the National Antimicrobial Resistance Monitoring System (NARMS) in cooperation with USDA-FSIS, USDA-APHIS, CDC and FDA. ARS determines the profile of antibiotic resistance of veterinary and slaughter bacterial pathogen isolates.

Summary of CSREES/ARS Collaborative Efforts

CSREES and ARS have been partners and strong participants in federal inter-agency food safety committees which have helped shape food safety policy.  They include the working groups that developed and wrote the Food Safety Strategic Plan and the work groups that helped develop and write the U.S. Public Health Plan to Combat Antimicrobial Resistance. Other continuing committees include the Risk Assessment Consortium and the Joint Institute for Food Safety Research Advisory Committee.  Both CSREES and ARS collaborated in FDA-CFSAN•s efforts to provide educational programs on the fresh fruit and vegetable guidelines.  This is an international effort and ARS and CSREES personnel have traveled to Mexico, Chile, New Zealand, South Africa and other countries to provide training.

Multi-state regional research committees provide coordination of various expertises among different states to address specific problems.  Both ARS and CSREES are members of these various committees and provide leadership.  These committees are important mechanisms to create networking and produce collaborative research opportunities. For example, there was a 2 day workshop last November to help strengthen the integration between the S-263 multi-state research group (Enhancing Food Safety through Control of Foodborne Disease) and the SERA-IEG2 information exchange extension group (food safety).  This meeting provided the opportunity for researchers and extension specialists to exchange information. There was a communication link-up to extension educators in participating states to increase the dissemination of information.

With ARS taking the lead, both ARS and CSREES help provide support to USDA•s regulatory arm, the Food Safety and Inspection Service.  For example, both CSREES and ARS provided scientists that described relevant research during a FSIS public meeting on proposed regulations of Listeria labeling for retail meats.  CREES has linked FSIS with 7 different universities through special grants to provide HACCP training to small and very small processors. CSREES has participated in the joint ARS/FSIS research planning meetings to determine the direction of food safety research.  Finally, ARS scientists have been able to combine research monies from ARS and grants from CSREES to advance food safety research.

Food safety will continue to remain a high priority with consumers, industry, and government.  The research, education, and extension programs described above are a brief summary of the many activities, but they provide a framework for continued collaborations between CSREES and ARS.  This partnership benefits other federal agencies and will continue to lead to future successes in food safety activities.