More than 150 students and staff at a school in Belgium fell ill during an outbreak of norovirus earlier this month, according to information recently released.

The Federal Agency for the Safety of the Food Chain (FASFC) reported the food poisoning at the Atheneum Pegasus school in the city of Ostend was caused by crudités, which are mixed raw vegetables.

The FASFC, known in French as AFSCA and Dutch as FAVV, was informed in early December about the incident and started investigating with Zorg en Gezondheid (The Agency for Care and Health), and Sciensano, the national reference laboratory, to determine the source of contamination.

A total of 71 students and some staff were absent on one day and complained of vomiting, abdominal pain and fever.

Tracing the source
Initial investigations showed sick students and staff had all eaten sandwiches. FASFC took four samples of leftover food from the school’s bins and seven samples from the unnamed supplier who delivered sandwiches to the school.

Norovirus was only found in raw vegetable samples. The virus detected in food was the same as that from patients’ stools, enabling the source of the outbreak to be named.

Jean-Sébastien Walhin, spokesperson for FASFC, said the investigation findings indicate that raw vegetables are the cause of food poisoning.

“Parents can be reassured, the incident has been resolved and FASFC continues to monitor the situation closely. We hope that in the meantime the 151 sick students and staff are fully back on their feet,” Walhin said.

Measures taken at the school and supplier level included toilets and rooms and tables where eating happens being disinfected. School staff and students were urged to pay attention to hand hygiene and those sick were asked to stay home until they had recovered.

The most common symptoms of norovirus are diarrhea, vomiting, nausea and stomach pain. A person usually develops symptoms 12 to 48 hours after being exposed to norovirus. Most people with illness get better within one to three days.

You can get norovirus by consuming contaminated food or liquids; touching contaminated surfaces or objects them putting your fingers in your mouth; or having direct contact with someone who is infected such as by sharing food or eating utensils with them. Only a few microscopic norovirus particles can make other people sick.

Online food sales
FASFC has also said it is paying close attention to online sales after a rise in apps that allow homemade food to be bought and sold. Dishes are offered for sale through websites, apps or social media platforms.

The agency said it cannot allow a two-tier system with the Horeca sector being severely affected by the coronavirus pandemic so amateur cooks and home chefs must meet the same requirements as professionals.

Amateur cooks who regularly prepare meals at home and sell them to other people are responsible for products sold and will be held to account if an incident occurs. It is mandatory to request authorization from FASFC before starting such sales. This includes an annual payment.

Some do not register with FASFC when their activity is no longer considered as occasional and non-profit, which is defined in regulation.

All cooks must inform customers about the presence of allergens; either verbally or in writing such as via the menu and put in place a system of self-control covering areas such as food traceability, personal hygiene, kitchen cleanliness and respect for expiration dates.

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