Further investigation led to suspicion of several pre-packaged lettuce mixes purchased in grocery stores. Preliminary investigations conducted at the Norwegian Veterinary Institute strengthened this suspicion. The manufacturer has therefore withdrawn a further nine lettuce mixes from the market. The Norwegian Food Safety Authority recommends that consumers should not eat these lettuce mixes. The Norwegian Institute of Public Health is continuing the investigation in co-operation with the Food Safety Authority and Veterinary Institute.
About the disease
Each year, 50-100 cases of yersiniosis are reported to the Norwegian Institute of Public Health. Most cases occur sporadically and several cases with a common source rarely occur in Norway.
Yersinia bacteria are transmitted primarily through food but can transmit between people in rare cases. The most common symptoms are diarrhoea, fever and abdominal pain, usually lasting for 1-3 weeks. In most cases, the disease clears up without treatment.
To avoid infecting others, it is important that people with diarrhoea are careful with hand washing after using the toilet and before cooking.
General preventive measures to avoid infection with Yersinia bacteria include:
- cook or fry raw pork/ pork products thoroughly
- avoid tasting raw, minced or ground meat
- wash vegetables
- avoid non-disinfected drinking water
- wash hands after using the toilet, after contact with animals and before cooking and eating
- wash knives, chopping boards and utensils that have been contaminated by raw foodstuff, especially pork.