The Environment Services of the City of Helsinki is investigating a number of suspected cases of food poisoning that are believed to be related to dining at several different restaurants and a pop-up event since the beginning of February. Currently, there are about 20 known cases of illness.

The individuals who have fallen ill all consumed oysters, and environmental services have taken food samples from the restaurants as well as patient samples from the city's epidemiological action. Norovirus has been found in the samples.

The Food Safety Unit is requesting that anyone who has eaten oysters at Fisken på Disken, Ravintola Natura, Ravintola Gillet, The Cock, Ravintola Meripaviljonki, and the pop-up event at Ravintola Sake bar & Izakaya in February 2023 and has fallen ill after their meal, to contact the food safety unit. Illnesses may also be linked to other restaurants.

Those who have fallen ill are encouraged to contact the food safety unit primarily through an electronic food poisoning form at Contact can also be made by phone on weekdays from 8 am to 4 pm at +358 9 310 31527.

Norovirus is the most common cause of sudden intestinal infections in Finland.

Oysters have previously been found to transmit norovirus infections. Oysters that are consumed raw or undercooked are common sources of transmission for epidemics because they filter noroviruses while living in water contaminated with human feces. Norovirus is destroyed when food is heated to +90 degrees Celsius for two minutes.

Norovirus is easily transmitted from person to person either directly or indirectly, for example, through contaminated surfaces. Norovirus can also spread easily through contaminated food or water. A very small amount of the virus is enough to cause infection. The incubation period for norovirus is usually 12-48 hours. Typical symptoms include diarrhea, nausea or vomiting, and often fever, abdominal pain, and cramps. Symptoms often start very suddenly and usually last for about 12-72 hours.

Some restaurants have already been inspected following the outbreak of food poisoning, and oyster importers have taken steps to recall their products.

Environmental services are investigating the epidemic in collaboration with the City of Helsinki's epidemiological action.