Occurrence: Generally in nature, in the bottom sludge in lakes and seas. Spore-forming bacteria, anaerobic. It can be found in fish products such as pickled herring and smoked fish in oil. It has also been found in other types of marinades such as olives, garlic and tomato pesto. If the bacteria is allowed to grow it forms a nerve poison which can lead to death if not treated in time.

Incubation: a few hours to several days, the symptoms usually appear after 12-36 hours.

Symptoms: initial; nausea and vomiting, followed by neurological symptoms; weakness, double vision, difficulty speaking and swallowing.

Reason for outbreaks: the bacteria is inhibited by acid, salt and low temperature. If you are careless with the amount of vinegar and salt and don’t store the food at low temperature, the bacteria grows and there is a risk that the food becomes toxic.

Prevention: follow the recipes carefully when pickling. Smoked fish should not be stored above +4 °C for more than three weeks.