A public health alert has been issued over contaminated frozen sweetcorn being sold in the UK that has led to NINE deaths.
Lab tests have found a food factory in Hungary was the source of an outbreak of listeriosis - and its contaminated products are being sold in shops in Britain and Northern Ireland.
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For most people the infection will cause vomiting and diarrhoea at worst but for those with weakened immune symptoms - such as babies, the elderly or pregnant women - it can be fatal.
There has been nine deaths across Europe, including two in the UK, over the last year or so that have been linked to listeriosis.
The European Food Safety Authority, Public Health England and the Food Standards Agency have now all issued public health advice following the outbreak.
They are advising that frozen sweetcorn should never be eaten past the sell-by date and it should be cooked first before adding to salads or other meals.
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Dr Kathie Grant, of Public Health England, said: "Most people won't have any symptoms of the infection or will only experience mild symptoms such as vomiting and diarrhoea, which usually pass within a few days without the need for treatment.
"More serious infection can develop in those with weakened immune systems or in vulnerable groups including babies, the elderly or pregnant women.
"The best way to prevent listeriosis is to practise good food hygiene.
"We are reminding people that most frozen vegetables, including sweetcorn, need to be cooked before eating.
"This includes if adding them to salads, smoothies or dips."
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The FSA said: "People should always follow manufacturers' instructions when preparing their food. If the product is not labelled as 'ready to eat', the cooking instructions should always be followed before eating the food hot or cold.
"Frozen sweetcorn is the likely source of an ongoing outbreak of listeriosis affecting five European countries including the United Kingdom.
"Listeriosis is a rare but serious foodborne illness caused by the bacterium Listeria monocytogenes that can be more serious for those individuals who have weakened immune systems and also the elderly, pregnant women and infants.
"The European Food Safety Authority and the European Centre for Disease Prevention and Control have today provided an update on the multi-country listeriosis outbreak."
The EFSA said the extent of the outbreak had initially been underestimated, and recent cases showed it was continuing.
Its report added: "It is strongly recommended that the processing plant concerned is completely cleaned and disinfected, which involves dismantling and thoroughly cleaning and disinfecting all the plant equipment, as well as any additional surfaces that may represent a point of contamination."