Foodborne Virus alerts in RASFF : an Update

In the past couple days, RASFF published two new informations for products contaminated with viruses in food (norovirus).

Noroviruses in French Oysters

As often published on this blog, oysters are a major source of contamination.

This is the eleventh RASFF alert on Molluscan shellfish this year. Overall oysters account for 46% of the foodstuff contaminated with norovirus.

Foodborne viruses and bivalve shellfish

Clams have also been implicated in alerts, with contamination by Hepatitis A Virus, and norovirus.

Pathogens and Foodstuff

Regulation (EC) No 852/2004 of the European Parliament and of the Council of 29 April 2004 on the hygiene of foodstuffs 

 

COMMISSION REGULATION (EC) No 2073/2005 of 15 November 2005 on microbiological criteria for foodstuffs :

(2) Foodstuffs should not contain micro-organisms or their toxins or metabolites in quantities that present an unacceptable risk for human health.

(27) In particular, criteria for pathogenic viruses in live bivalve molluscs should be established when the analytical methods are developed sufficiently. There is a need for development of reliable methods for other microbial hazards too, e.g. Vibrio parahaemolyticus.

Noroviruses in Bulgarian Raspberries

Fruits are the most second foodstuff implicated in outbreak, and rapsberries have been recently implicated with a contamination by Norovirus.
Products from Bulgaria has been implicated 10 times in alerts, essnetially for Hepatitis A Virus. This is the first time that norovirus, according to the RASFF, is detected in fruits from Bulgaria.
Italy, France and Norway have posted those alerts in the past years.

Foodborne virus and ISO Method

In 2014, 15% of the RASFF virus alerts implicated fruits. ISO Method is available for the pre-treatment of various matrices, including Fruits (stoneless edible fruits), such as raspberries, strawberries, blackberries, blueberries, pomegranate seeds, currants.

• ISO/TS 15216

  ISO/TS 15216-1:2013 describes a method for quantification of levels of :
  ISO/TS 15216-2:2013 describes a method for qualitative detection of :
  
  
  1. HAV (Hepatitis A Virus) and
  2. NoV ( Norovirus) genogroup I (GI) and II (GII) RNA,

from test samples of foodstuffs or food surfaces. Following liberation of viruses from the test sample, viral RNA is then extracted by lysis with guanidine thiocyanate and adsorption on silica. Target sequences within the viral RNA are amplified and detected by real-time RT-PCR.

Hepatitis A Virus and Norovirus

• 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

Sources :

1. RASFF
2. CDC: http://www.cdc.gov/hepatitis/HAV/index.htm
3. WHO: http://www.who.int/csr/disease/hepatitis/whocdscsredc2007/en/index2.html