Leafy greens and Foodborne viruses

There is now a long history of foodborne virus contamination of vegetables in the form of leaf, and through the RASFF (Rapid Alert System for Food and Feed), that can be traced back to 2010.

Norovirus and Hepatitis A virus in Lettuce

No less than four alerts have been registered in the RASFF over a period of 6 years, not only for norovirus but also Hepatitis A Virus. Produces were originating from Germany, Hungary, France (2 times). Romaine lettuce, iceberg lettuce and lettuce (Lactuca sativa) were the varieties implicated.

Norovirus contaminates French lettuce

The latest RASFF alert concerns french lettuce delivered to Denmark and Norway, controled positive for Norovirus GII, and withdrawn from the market.

EFSA Scientific Opinion : Norovirus and Leafy Greens

As stated by EFSA in 2014, appropriate implementation of food safety management systems, including Good Agricultural Practices (GAP), Good Hygiene Practices (GHP) and Good Manufacturing Practices (GMP), should be primary objectives of leafy green producers.

FCD : a foodborne virus initiative

In France, FCD (Federation of Commerce and Distribution) has implemented in 2015 in its recommendations for microbiological criteria control plans, norovirus and hepatitis A virus :

ISO/TS 15216 and Foodborne virus

A method exists for the detection, identification and quantification of norovirus and hepatitis A virus in salad vegetable, with standardized protocols for the elution of those viruses from leafy greens.

What are food-borne viruses?

• HAV was first identified in 1973, and is a non-enveloped virus, classified within the genus hepatovirus of the picornavirus family. Hepatitis A is a liver infection caused by the Hepatitis A virus (HAV). Hepatitis A is highly contagious. HAV is  transmitted by the fecal-oral route, either through person-to-person contact orconsumption of contaminated food or water. For more information on Hepatitis A check the CDC website and WHO Website.
• Noroviruses are highly contagious and 10-100 viral particles may be sufficient to infect an individual. They are transmitted primarily through the faecal-oral route, either by consumption of contaminated food or water, or by spreading directly from person to person. Vomiting creates aerosols with high content of virus particles, which enter the oral mucosa or contaminate surfaces. The virus survives a long time on different surfaces and thus, environment may serve as a source of new infections. For more information on norovirus check the ECDC website