The number of people in France who have become ill after eating contaminated raw shellfish has jumped to more than 1,000. The outbreak has spurred international recalls.

A total of 1,033 people have been sickened and 21 needed hospital treatment, according to Santé publique France. A previous update listed the number of illnesses at 668.

Sweden, Italy and the Netherlands have all also reported outbreaks linked to live oysters from France. Products have been recalled due to a risk of norovirus contamination in Luxembourg, Switzerland, Hong Kong and Singapore.

Mats Lindblad, a communicable disease coordinator at Livsmedelsverket (National Food Agency of Sweden), said 31 people are sick in the country.

“The link was made by patient interviews. Symptoms and incubation time indicate norovirus. Livsmedelsverket has not issued any advice against eating oysters. We will, however, inform consumers about the unusually high number of food poisonings related to oysters in Sweden and other countries this winter,” he told Food Safety News.

The outbreak appears to be limited in the Netherlands to the Amsterdam area of the country.

More ill than past years
Since early December 2019, Santé publique France has received 179 reports of collective food poisoning suspected to be linked to consumption of raw shellfish but mainly oysters.

Most reports, 138 of the 179 alerts, occurred beginning Dec. 23, 2019, and onward with a peak of illnesses from December 25 to 27. Of the 595 patients with age information only 19 were children under 15 years old.

Symptoms such as diarrhea and vomiting and incubation times, are consistent with norovirus or other enteric virus infections. Stool tests have confirmed presence of these viruses. Symptoms of norovirus appear one to two days after being infected and typically last for two or three days. Norovirus is transmitted by having contaminated food or water or from person to person through contact with the skin, objects or inhaling airborne particles. The virus can live for long periods of time on surfaces such as counters and door knobs.

The number of notifications linked to consumption of raw shellfish in 2019 is higher than previous years. Annually between 25 and 120 alerts related to eating shellfish are reported to Santé publique France, of which between four and 30 occur between December and January.

French authorities are tracing back contaminated items to production areas and testing the sites concerned. To date, several areas have been closed because of contamination by norovirus.

Authorities in Ille-et-Vilaine in France stopped fishing, collection, shipping and marketing of shellfish from two production areas. These are “Baie du Mont Saint-Michel rivage” and “Zone conchylicole d’Hirel but the latter has been lifted.

A number of supermarket chains in France have informed consumers of recalls because of possible norovirus in products from companies including Cultimer France, La Vivière, Thaëron, Mytilimer Production, Les Viviers de Saint Colomban et Keroma, Huitres Henry and Fine de Cancale.

Officials from the Ministry of Agriculture and Food said recent heavy rain, the normal winter spike of norovirus and a period of high shellfish consumption contributed to the increase in illnesses. They said preventing contamination by strengthening the monitoring of wastewater treatment is crucial and is the responsibility of local authorities.

A total of 23 shellfish growing zones in seven regions of France have been closed with more than 400 companies affected, according to the agency. One contaminated area is closed for 28 days.

EU and Asia recalls
In Belgium, Match and Cora recalled mussels branded “Moules de Bouchot de la Baie du Mont Saint Michel” from some stores.

In Luxembourg, Auchan sold oysters and mussels from the companies Mytilimer, SAS Kermaree and Cultimer that have been recalled. Cora also recalled two products for the same reason.

Certain Aligro, Coop, the Manor Supermarket in Lausanne, and the Migros store in Geneva issued recalls for mussels, cockles and oysters in Switzerland.

The Centre for Food Safety in Hong Kong found a local firm had imported affected not ready-to-eat mussels which were on sale in its supermarkets. The agency has suspended the import and sale within Hong Kong of all shellfish harvested in the two French areas concerned.

In Singapore, “Bouchot live mussels” from France (Baie Du Mont-Saint-Michel) were recalled due to norovirus. The Singapore Food Agency told the importer, Classic Fine Food(s) Pte Ltd, to recall the products which are no longer available on the market.

Potentially contaminated products have also been distributed to Austria, Denmark, China, Czech Republic, Finland, Germany, Latvia, Lithuania, Japan, Malta, Poland, Spain and Ukraine, according to alerts on the RASFF portal.

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