Performing Department
(N/A)
Non Technical Summary
Fresh and frozen produce contaminated with viruses causes illness in consumers and harm to the produce industry. Laboratory tests for produce can detect virus pieces on produce but cannot tell if the virus pieces are infectious and will make consumers sick. Our first objective is to develop improved laboratory tests for produce, such as raspberries and lettuce, to tell if detected virus is infectious. One way is by adding a biological step that destroys non-infectious virus and retains infectious virus for detection. By adding this biological step, we will improve a currently used commercial laboratory test. Our second objective is to test whether a commercially available machine can destroy viruses on produce without damaging the produce. Our third objective is to use math models to see if the tests we develop in this proposal are better than existing tests at predicting outbreaks. This project will protect consumers from infectious viruses on produce. This project will also help the produce industry keep safe produce on shelves, focus recall and destruction activities on produce with infectious virus, and reduce waste from unnecessarily recalled produce.
Animal Health Component
50%
Research Effort Categories
Basic
(N/A)
Applied
50%
Developmental
50%
Goals / Objectives
This applied research project addresses PA 1332's priority to "reduce the risk of intentional or unintentional contamination of foods" in the produce supply chain. Our long-term goal is to develop comprehensive tools for the produce industry, government, and academia to prevent US enteric viral produce outbreaks. As produce safety risks associated with hepatitis A (HAV) and human norovirus increase from a globally sourced produce sector, several technical issues have emerged related to their detection and inactivation. Stakeholders urgently need comprehensive tools to enhance their ability to: (1) detect infectious viruses on produce; (2) inactivate infectious viruses on produce; and (3) implement risk-based decisions that safeguard both US consumers and the US produce industry. Our objectives are to:Validate human norovirus and hepatitis A virus (HAV) infectivity assays on at-risk commodities including frozen raspberries and fresh lettuce.Evaluate a commercially available non-thermal inactivation strategy against human norovirus and HAV on frozen raspberries and fresh chopped lettuce.Model whether standard RT-qPCR based versus infectivity-based viral assays in produce testing help predict the occurrence of viral outbreaks.
Project Methods
OBJECTIVE 1 METHODS. Validate human norovirus and hepatitis A virus (HAV) infectivity assays on at-risk commodities including frozen raspberries and fresh lettuce.Quantify the recovery of HAV and human norovirus inocula from inoculated frozen raspberry and fresh lettuce.Compare results between two infectivity assays with cell culture and human infection data.OBJECTIVE 2 METHODS. Evaluate a commercially available non-thermal inactivation strategy against human norovirus and HAV on frozen raspberries and fresh chopped lettuce.Evaluate the effect of commercially available Clean Works technology on virally innoculated frozen raspberries and lettuceSummarize the state-of-the-field for enteric virus inactivation technologies, gaps, and recommendations for produce industry-initiated next stepsOBJECTIVE 3 METHODS. Model whether standard RT-qPCR-based versus infectivity-based viral assays in produce testing better predict the occurrence of viral outbreaks.Develop HAV and human norovirus GI, GII QMRA frameworks to compare standard RT-qPCR-based versus infectivity-based viral assays in produce testingIntegrate the QMRA into the IDT model to simulate transmission among produce consumer populations.