The U.S. Food and Drug Administration (FDA) has published a new commodity-specific prevention strategy for norovirus and hepatitis A virus contamination of fresh and frozen berries.

According to a 2024 report by the Food and Agriculture Organization of the United Nations (FAO)/World Health Organization (WHO) Joint Expert Meeting on Microbiological Risk Assessment, frozen berries contaminated with hepatitis A virus and norovirus are virus-commodity pairs that present the highest global public health burden. In the U.S., outbreaks of these enteric viruses have been linked to imported fresh and frozen berries since 1997, with the most recent berry-associated hepatitis A outbreaks occurring in 2022 and 2023.

Based on findings from outbreak investigations, historical data, and consultations with food safety experts, the prevention strategy addresses factors that may contribute to the contamination of berries with enteric viruses, and outlines actions for FDA and industry to mitigate enteric virus contamination of berries, such as:

• Promoting high rates of compliance with FDA food safety requirements
• Encouraging industry to identify and ensure consistent application of processes, or a combination of processes, which describe adequate berry pre- and post-harvest sanitary practices for domestic and global berry operations, including promoting the use of root cause analysis when failures are observed in food safety systems
• Broadening scientific knowledge about the viability, persistence, detection, and mitigation of viruses in fresh and frozen berries, pre- and post-harvest environments, and agricultural water sources
• Incentivizing industry and governments to embrace the use of public health prevention measures through immunization programs to promote worker health.

Key factors to consider in preventing berry-associated enteric virus outbreaks include proper hygienic practices of field workers, management of sanitary facilities, measures to prevent cross-contamination of fruit in the field and processing operations, and measures to monitor and limit viral carriage of farm and facility workers. Further investigation is needed to better understand viral persistence in the agricultural environment, the processing environment, and in berries; routes of contamination; and public health factors.

FDA’s prevention strategy addresses critical knowledge gaps by fostering scientific research to enhance the ability to detect and characterize enteric viruses in various sample types and link sources of contamination using advanced laboratory methods. Research also focuses on understanding the ecology of enteric viruses in berry and other fresh produce operations. All defined goals and deliverables aim to reduce future incidences of foodborne illness linked to fresh and frozen berries.

For a discussion with an FDA official and produce expert about FDA’s approach to commodity-specific prevention strategies for foodborne illnesses associated with produce, listen to this bonus episode of the Food Safety Matters podcast.