Food-safety experts have issued a warning over smoked fish, as eight cases have been identified in England and Scotland since 2022.
Ian McWatt, Food Standards Scotland (FSS) Deputy Chief Executive, said: "While the risks to the general public of becoming seriously ill due to listeria are very low, we need people who are vulnerable to be aware of the ongoing risks of consuming ready-to-eat smoked fish.
He added: "If anyone from these groups is eating ready-to-eat smoked fish, we are reminding them of the advice to ensure that it is thoroughly cooked before they eat it, including when served as part of a dish.
"People can also further reduce the risk by keeping chilled ready-to-eat smoked fish cold (5â°C or below), always using products by their use-by date, following the storage instructions on the label, and cooking it until it is pipin- hot right through."
The NHS says: "Due to a listeria outbreak linked to smoked fish, people at higher risk of serious infection should only eat smoked-fish products that have been thoroughly cooked.
"When cooking smoked-fish products at home, make sure they are steaming hot all the way through."
Listeriosis is a rare infection caused by listeria, and it is usually caught from eating food that contains the bacteria.
It mainly happens in chilled ready-to-eat foods, such as smoked fish and shellfish, sliced meats, soft cheeses, sandwiches, fruit, and unpasteurised milk.
Listeriosis doesn't always cause symptoms, but when it does, they include a high temperature of 38C or above, aches and pains, chills, feeling or being sick, and diarrhoea. These symptoms usually last for a few days.
Listeriosis isn't always serious, but some people are at a higher risk of developing serious problems, like meningitis and life-threatening sepsis.
These at-risk groups include pregnant women, newborn babies, people aged 65 or over, people with a weakened immune system, and people with uncontrolled diabetes.
People in the aforementioned at-risk groups should contact the NHS on 111 if they think they have listeriosis.
People should call 999 or go to A&E if they have any of the following symptoms:
These could be symptoms of meningitis caused by listeriosis.
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