Federal officials are collecting 2,000 samples of frozen berries produced in and imported to the United States as part of an effort to develop preventive controls against pathogens such as hepatitis A and norovirus.

The two viruses caused outbreaks in recent years that sickened hundreds of people across the United States. In some outbreaks retailers sold contaminated berries directly to consumers. In other instances, such as the 2016 outbreak traced to Tropical Smoothie Cafe locations, domestic entities bought imported berries in bulk and used them as ingredients in their products.

Berries are served raw alone and in various receipies, without a cooking kill step, the vast majority of the time, making them more dangerous in terms of foodborne pathogens than many other domestic and imported foods, according to an announcement today from the Food and Drug Administration.

The agency reported that the testing program began in November 2018. Results will be posted for public view on a quarterly basis during the “sampling assignment,” which will likely take about 18 months to complete. A final analysis is planned after the data is reviewed. 

“The agency is collecting domestic samples of frozen berries in retail packaging from processors, distribution centers, warehouses, and retail locations,” according to the announcement. “The agency is also collecting import samples from ports of entry, importer warehouses, or other storage facilities where foreign goods are cleared for entry into the country. The FDA plans to collect and test 2,000 samples in all.

“Strawberries, raspberries and blackberries are delicate and may become contaminated with bacteria or viruses if handled by an infected worker who does not use appropriate hand hygiene, or if exposed to contaminated agricultural water or a contaminated surface, like a harvesting tote. 

“Freezing preserves berries but generally does not kill viruses, which can survive at low temperatures.”

The average number of annual hepatitis A virus infections reported to the Centers for Disease Control and Prevention in recent years declined compared to 2000, but fluctuations have occurred in the last 20 years because large outbreaks occurred. The first increase was in 2012-13 when there were 1,562 and 1,781 reported cases, respectively. The multi-state outbreak associated with pomegranate arils imported from Turkey. 

Between 2015 and 2016, the reported U.S. case patients increased by 44.4 percent from 1,390 in 2015 to 2,007 cases in 2016. The 2016 increase was because of two hepatitis A outbreaks, each of which was linked to imported foods, according to the CDC. The FDA’s announcement cited outbreaks logged from 1997 through 2016.

If laboratory tests from the current sampling program confirm hepatitis A virus or norovirus in a sample, the FDA will notify the firm of the findings and work with the business owners to take appropriate action to protect the public health. 

The U.S. agency may also take actions such as placing companies on an import alerts; oversee recalls; or issuing public warnings. For example, in 2018 the FDA banned the import of frozen strawberries from a company in Egypt because it was a supplier to the Tropical Smoothie Cafe chain.

There is also growing concern about frozen berries among public health officials in other countries. A large hepatitis A outbreak linked to mixed frozen berries in Europe in 2013 and 2014 caused more than 1,500 illnesses. In 2018 the Food Safety Authority of Ireland reiterated advice to boil imported frozen berries before eating following multiple alerts across Europe for Hepatitis A and norovirus exposures.

Similar to frozen berries, frozen pomegranate arils have been linked to outbreaks in the United States and around the world, including one in Australia this past year.

FDA posts answers to anticipated questions

When will the FDA collect samples?
The FDA plans to collect samples throughout the year, across all seasons. … Samples may be collected from the same establishment or importer on more than one occasion. To minimize impact on any one firm, the FDA will not exceed three collections every six months from the same establishment, as a general rule, assuming no violations are found.

What exactly do you plan to collect?
The agency will only collect frozen strawberries, frozen raspberries, and frozen blackberries in retail packaging.

Will the FDA provide pre-notification to facilities where it plans to conduct sampling
Per standard FDA practice, the agency will not provide pre-notification to firms prior to collecting samples, to preserve the study’s integrity. Sampling is a routine and critical activity that the agency is authorized to conduct to help ensure the safety of the food supply.

What is the FDA doing to minimize the impact of its sampling on industry and commerce?
The FDA is sensitive to the concerns of domestic firms and importers and strives to provide analytical results to industry as soon as they are available. The FDA will notify firms of all analytical results as soon as possible once sample analysis is complete.

Reports from other FDA sampling programs in recent years

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