The U.S. Food and Drug Administration (FDA) has announced a comprehensive strategy to prevent outbreaks of hepatitis A virus (HAV) and norovirus (NoV) linked to fresh and frozen berries, following recent contamination incidents involving imported products.
The initiative comes in response to HAV outbreaks in 2022 and 2023 traced to berries from a single international supplier. While domestic berry production has maintained a strong safety record with no reported enteric (of, relating to, or affecting the intestines) virus outbreaks in 35 years, imported berries have been associated with several incidents since 1997.
The significance of addressing viral contamination in berries was underscored by a 2023 joint expert panel of the Food and Agriculture Organizations of the United Nations and World Health Organization. The panel identified HAV and NoV contamination in frozen berries as one of the “highest global public health burden” concerns among virus-food combinations.
Conrad Choiniere, Director of the Office of Microbiological Food Safety at the FDA’s Human Food Program, emphasized the collaborative nature of the initiative: “Collaboration between regulators, the global berry industry, and other interest holders has been critical for the development of this strategy.”
The FDA’s prevention strategy focuses on several key areas of concern identified through outbreak investigations and consultations with industry food safety experts. These include proper hygiene practices for field workers, management of sanitary facilities, and measures to prevent cross-contamination during both field and processing operations.
A particular challenge in preventing viral contamination is that individuals can spread these viruses before showing any symptoms or without developing symptoms at all. This characteristic highlights the crucial importance of maintaining consistent sanitary controls throughout the production process.
Hepatitis A virus, while typically causing a short-term infection from which people fully recover within weeks, can pose serious risks to certain populations. Older individuals, those with compromised immune systems, people with chronic liver disease, and those with underlying health conditions may face more severe complications, including potential liver failure. Common symptoms include fatigue, nausea, vomiting, abdominal pain, jaundice, dark urine, and pale stool.
Norovirus, according to the Centers for Disease Control and Prevention (CDC), typically spreads in healthcare facilities, restaurants, catered events, schools, childcare centers, and cruise ships. However, contamination can occur at any point in the food supply chain, including at the farm level. In response to this risk, the FDA has developed an Employee Health Policy Tool as part of the Healthy People 2030’s norovirus workgroup initiative.
The FDA’s new strategy outlines specific actions for both the agency and industry stakeholders. Key elements include:
- Ensuring high compliance rates with FDA food safety requirements
- Supporting the berry industry in developing and implementing effective pre- and post-harvest sanitary practices for both domestic and international operations
- Expanding scientific understanding of how viruses survive and spread in berries and agricultural environments
- Encouraging the adoption of public health prevention measures, including immunization programs for workers
The initiative also addresses knowledge gaps through enhanced scientific research. This includes improving methods for detecting and characterizing enteric viruses in various sample types and developing better techniques for tracing contamination sources using advanced laboratory methods.
Food safety experts note that contamination often results from breakdowns in food safety systems and prevention methods. The FDA’s strategy emphasizes the importance of monitoring and limiting viral carriage among farm and facility workers while maintaining strict hygienic practices throughout the production process.
The plan acknowledges that food safety requires cooperation throughout the supply chain. Growers and processors bear responsibility for delivering safe produce that meets relevant food safety requirements. By identifying and sharing effective food safety practices specific to fresh and frozen berry operations, the FDA aims to benefit operators throughout the global berry industry while providing insights that could improve controls for other fresh and frozen produce with similar risk factors.
Research priorities under the new strategy include studying viral persistence in agricultural environments, processing facilities, and berries themselves. Scientists will also investigate various routes of contamination and examine public health factors that contribute to outbreaks.
The FDA developed this prevention strategy to address factors that may lead to enteric virus contamination in berries while ensuring accurate and timely communication across the global berry industry. The ultimate goal is to reduce future incidents of foodborne illness linked to both fresh and frozen berries through consistent application of effective prevention measures.
Commenting on this article, the nation’s leading hepatitis A and norovirus lawyer said, “By combining enhanced safety protocols, scientific research, and industry collaboration, the safety of both domestic and imported berry products for American consumers should be greatly enhanced.”