Norovirus in fresh produce – implications for the food industry and its regulators

D'Agostino, Martin (2023) Norovirus in fresh produce – implications for the food industry and its regulators. PhD thesis, University of Liverpool.

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Abstract

This PhD thesis addresses the significant issues surrounding the detection of viral RNA on fresh produce, with a primary focus on norovirus and its implications for the fresh produce industry. It explores the impact of accurate interpretation of norovirus (including hepatitis A virus) RNA detection on fresh and frozen produce and how this should shape the acceptance of molecular-based detection methods in the food industry and helping inform the development of crucial microbiological regulations by food safety authorities. The thesis focuses on two pivotal questions: What does the detection of norovirus RNA in fresh and/or frozen produce imply about potential health risks? And how should the industry respond to a positive result? These questions have practical implications, influencing the acceptance of molecular-based detection methods in the food industry and the development of microbiological regulations by food safety authorities. While not the primary focus of this thesis, it is important to note that the principles discussed can also be applied to hepatitis A virus, as it shares common transmission routes with norovirus. The research presented in this thesis builds upon years of investigation in the field. It acknowledges the transformation from a lack of fundamental knowledge about foodborne viruses, to a deeper understanding of transmission routes and their impact on food supply chains. Despite this progress, a significant challenge lies in the general unwillingness to confront the issue head-on, fuelled by a lack of transparency throughout the food supply chain. One example of this is the limited accessibility of information regarding irrigation water practices across the UK, specifically in terms of the irrigation of fresh produce crops and the microbiological quality of the water used. This lack of transparency hampers our awareness of the potential risks posed by viral contamination originating from irrigation water and its impact on fresh produce. Furthermore, there is a prevailing fear within the food industry of openly addressing and communicating issues related to product contamination, undermining the necessary transparency and effective response. In light of these challenges, the thesis emphasises the critical importance of fostering transparency, improved communication and further raising awareness of foodborne viruses within the industry. It calls for a more comprehensive understanding of irrigation practices, including the virological quality of water used in fresh produce cultivation, not only locally but wherever our fresh and frozen produce is sourced. Additionally, it highlights the need for proactive measures to address the risks associated with viral contamination, ensuring the safety and integrity of fresh produce. By addressing these complex issues, this research contributes to the advancement of knowledge and practices in detecting and mitigating viral RNA on fresh produce. It underscores the necessity of a collaborative approach that embraces transparency, communication and informed decision-making across the entire food supply chain.

Item Type:	Thesis (PhD)
Divisions:	Faculty of Health and Life Sciences
Depositing User:	Symplectic Admin
Date Deposited:	01 Feb 2024 16:49
Last Modified:	01 Feb 2024 16:49
DOI:	10.17638/03176707
Supervisors:	O'Brien, Sarah Cook, Nigel Fisher, Peter
URI:	https://livrepository.liverpool.ac.uk/id/eprint/3176707