This study aims to review the US FSIS farm-to-table risk assessment model for Salmonella enteritidis in eggs and egg products in order to address the following questions:<ul>
<li>What are the key strengthens and weaknesses of this analysis?
<li>How appropriate is the use of Monte Carlo simulation and a highly detailed spreadsheet?
<li>What alternative methodologies, if any, would be appropriate?
<li>Which aspects of the model would not be readily transferable to the UK context, and why not?
<li>What would be required to apply this methodological approach to the UK, and what are the resource requirements likely to be? </li> </ul>
The outputs of this study will inform the work being undertaken in a risk assessment by a working group of the Advisory Committee on the Microbiological Safety of Food (ACMSF).
This research project aims to review the US Food Safety and Inspection Service (FSIS) farm-to-table risk assessment model for Salmonella enteritidis in eggs and egg products.
<p>The FSIS farm-to-table risk assessment model for Salmonella enteritidis in eggs and egg products comprises the following modules: production, shell eggs processing and distribution, egg products processing and distribution, preparation and consumption, and public health outcomes. <p>These modules are represented by a number of worksheets and tables within the spreadsheet model and there is not necessarily a direct mapping between modules and worksheets.
<p>The model comprises the following worksheets:<ul>
<li>Summary - a series of tables provide the user with key model outputs and allows input of key assumptions.
<li>ProdModel - represents the production model.
<li>Model - a set of tables representing the shell eggs processing and distribution, egg products processing, distribution, preparation and consumption modules and the mitigation of risk for each of these modules.
<li>PublicHealth - represents the Public Health Outcomes modules.
<li>Paths - summarises data for the preparation and consumption module in terms of possible egg preparation and use.</li> </ul>
<p>The immense size and complexity of both the model and its associated worksheets and tables means that it is not easy for a user unfamiliar with the structure of the model to navigate from one area to another.
<p>The overall structure of the model and the input data required to run it reflects the US requirement to establish the risk of foodborne illness for Salmonella enteritidis infected eggs and strategies to mitigate these risks.
The model concentrates solely on the internal contamination of the egg via ovarian transmission, hence excludes consideration of shell-borne organisms.
Therefore the current US model does not take into account contamination of egg contents by shell fragments during breaking, or cross-contamination due to, for example, poor hygiene or the use of contaminated utensils during food preparation. It also appears that the US model does not consider imported eggs.
<p>The mitigation parameters in the model allow a simple representation of risk mitigation, modifying both results calculated by the baseline model tables and relevant input data with the intention of reducing the number of human illness outcomes. It is not possible to use the model to examine or compare the cost/effectiveness of any specific mitigation strategy.
<p>Find more about this project and other FSA food safety-related projects at the <a href="http://www.food.gov.uk/science/research/" target="_blank">Food Standards Agency Research webpage</a>.